{ "slug": "radix-sort", "title": "Radix Sort", "category": "Sorting", "difficulty": "hard", "complexity": { "time": "O(d · (n + b))", "space": "O(n + b)" }, "idea": "Sort the numbers by their last digit, then the next digit, and so on. Each pass is a stable counting sort on one digit (base 10). After the most-significant digit, the whole array is sorted.", "code": [ "for each digit position (1s, 10s, 100s, …):", " count how many numbers have each digit 0–9", " running-sum the counts into positions", " place numbers into output by that digit (stable)", " copy output back into the array" ], "example": { "array": [ 170, 45, 75, 90, 24, 2, 66 ] }, "invariant": "Each step is the real data structure at that step — the picture is a pure function of it.", "stepCount": 53, "steps": [ { "i": 0, "op": "lanes", "caption": "Radix sort: stably sort by each digit, least-significant first.", "note": null, "codeLine": null, "stats": null, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 1, "op": "lanes", "caption": "Pass 1: sort by the ones digit.", "note": null, "codeLine": 1, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 2, "op": "lanes", "caption": "170: ones digit is 0 → counts[0] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ "read", null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 ], "focus": [ "write", null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 3, "op": "lanes", "caption": "45: ones digit is 5 → counts[5] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, "read", null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 0, 0, 0, 1, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, "write", null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 4, "op": "lanes", "caption": "75: ones digit is 5 → counts[5] = 2.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, "read", null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 0, 0, 0, 2, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, "write", null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 5, "op": "lanes", "caption": "90: ones digit is 0 → counts[0] = 2.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, "read", null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 0, 0, 0, 0, 2, 0, 0, 0, 0 ], "focus": [ "write", null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 6, "op": "lanes", "caption": "24: ones digit is 4 → counts[4] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, "read", null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 0, 0, 0, 1, 2, 0, 0, 0, 0 ], "focus": [ null, null, null, null, "write", null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 7, "op": "lanes", "caption": "2: ones digit is 2 → counts[2] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, "read", null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 0, 1, 0, 1, 2, 0, 0, 0, 0 ], "focus": [ null, null, "write", null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 8, "op": "lanes", "caption": "66: ones digit is 6 → counts[6] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, null, "read" ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 0, 1, 0, 1, 2, 1, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, "write", null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 9, "op": "lanes", "caption": "Running-sum the digit counts into positions.", "note": null, "codeLine": 3, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 2, 3, 3, 4, 6, 7, 7, 7, 7 ], "focus": [ "read", "read", "read", "read", "read", "read", "read", "read", "read", "read" ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 10, "op": "lanes", "caption": "Place 66 at output[6] (digit 6).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, null, "read" ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 2, 3, 3, 4, 6, 6, 7, 7, 7 ], "focus": [ null, null, null, null, null, null, "write", null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 66 ], "focus": [ null, null, null, null, null, null, "insert" ], "placeholders": [ true, true, true, true, true, true, false ], "markers": [], "regions": [] } ] }, { "i": 11, "op": "lanes", "caption": "Place 2 at output[2] (digit 2).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, null, "read", null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 2, 2, 3, 4, 6, 6, 7, 7, 7 ], "focus": [ null, null, "write", null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 2, 0, 0, 0, 66 ], "focus": [ null, null, "insert", null, null, null, null ], "placeholders": [ true, true, false, true, true, true, false ], "markers": [], "regions": [] } ] }, { "i": 12, "op": "lanes", "caption": "Place 24 at output[3] (digit 4).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, null, "read", null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 2, 2, 2, 3, 3, 6, 6, 7, 7, 7 ], "focus": [ null, null, null, null, "write", null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 2, 24, 0, 0, 66 ], "focus": [ null, null, null, "insert", null, null, null ], "placeholders": [ true, true, false, false, true, true, false ], "markers": [], "regions": [] } ] }, { "i": 13, "op": "lanes", "caption": "Place 90 at output[1] (digit 0).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, null, "read", null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 2, 2, 3, 3, 6, 6, 7, 7, 7 ], "focus": [ "write", null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 90, 2, 24, 0, 0, 66 ], "focus": [ null, "insert", null, null, null, null, null ], "placeholders": [ true, false, false, false, true, true, false ], "markers": [], "regions": [] } ] }, { "i": 14, "op": "lanes", "caption": "Place 75 at output[5] (digit 5).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, null, "read", null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 2, 2, 3, 3, 5, 6, 7, 7, 7 ], "focus": [ null, null, null, null, null, "write", null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 90, 2, 24, 0, 75, 66 ], "focus": [ null, null, null, null, null, "insert", null ], "placeholders": [ true, false, false, false, true, false, false ], "markers": [], "regions": [] } ] }, { "i": 15, "op": "lanes", "caption": "Place 45 at output[4] (digit 5).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ null, "read", null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 2, 2, 3, 3, 4, 6, 7, 7, 7 ], "focus": [ null, null, null, null, null, "write", null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, "insert", null, null ], "placeholders": [ true, false, false, false, false, false, false ], "markers": [], "regions": [] } ] }, { "i": 16, "op": "lanes", "caption": "Place 170 at output[0] (digit 0).", "note": null, "codeLine": 4, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 45, 75, 90, 24, 2, 66 ], "focus": [ "read", null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 2, 2, 3, 3, 4, 6, 7, 7, 7 ], "focus": [ "write", null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ "insert", null, null, null, null, null, null ], "markers": [], "regions": [] } ] }, { "i": 17, "op": "lanes", "caption": "Copy the output back — the array is now sorted by the ones digit.", "note": null, "codeLine": 5, "stats": { "pass": 1 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ "write", "write", "write", "write", "write", "write", "write" ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 2, 2, 3, 3, 4, 6, 7, 7, 7 ], "focus": [ null, null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, null, null, null ], "markers": [], "regions": [] } ] }, { "i": 18, "op": "lanes", "caption": "Pass 2: sort by the tens digit.", "note": null, "codeLine": 1, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 19, "op": "lanes", "caption": "170: tens digit is 7 → counts[7] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ "read", null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 0, 0, 0, 0, 0, 0, 1, 0, 0 ], "focus": [ null, null, null, null, null, null, null, "write", null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 20, "op": "lanes", "caption": "90: tens digit is 9 → counts[9] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, "read", null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 0, 0, 0, 0, 0, 0, 0, 1, 0, 1 ], "focus": [ null, null, null, null, null, null, null, null, null, "write" ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 21, "op": "lanes", "caption": "2: tens digit is 0 → counts[0] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, "read", null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 0, 0, 0, 0, 0, 1, 0, 1 ], "focus": [ "write", null, null, null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 22, "op": "lanes", "caption": "24: tens digit is 2 → counts[2] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, "read", null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 1, 0, 0, 0, 0, 1, 0, 1 ], "focus": [ null, null, "write", null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 23, "op": "lanes", "caption": "45: tens digit is 4 → counts[4] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, "read", null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 1, 0, 1, 0, 0, 1, 0, 1 ], "focus": [ null, null, null, null, "write", null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 24, "op": "lanes", "caption": "75: tens digit is 7 → counts[7] = 2.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, null, "read", null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 1, 0, 1, 0, 0, 2, 0, 1 ], "focus": [ null, null, null, null, null, null, null, "write", null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 25, "op": "lanes", "caption": "66: tens digit is 6 → counts[6] = 1.", "note": null, "codeLine": 2, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, null, null, "read" ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 0, 1, 0, 1, 0, 1, 2, 0, 1 ], "focus": [ null, null, null, null, null, null, "write", null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 26, "op": "lanes", "caption": "Running-sum the digit counts into positions.", "note": null, "codeLine": 3, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, null, null, null ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 1, 2, 2, 3, 3, 4, 6, 6, 7 ], "focus": [ "read", "read", "read", "read", "read", "read", "read", "read", "read", "read" ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 0, 0, 0, 0 ], "focus": [ null, null, null, null, null, null, null ], "placeholders": [ true, true, true, true, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 27, "op": "lanes", "caption": "Place 66 at output[3] (digit 6).", "note": null, "codeLine": 4, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 24, 45, 75, 66 ], "focus": [ null, null, null, null, null, null, "read" ], "markers": [], "regions": [] }, { "id": "count", "label": "digit counts (0–9)", "array": [ 1, 1, 2, 2, 3, 3, 3, 6, 6, 7 ], "focus": [ null, null, null, null, null, null, "write", null, null, null ], "markers": [], "regions": [] }, { "id": "out", "label": "output", "array": [ 0, 0, 0, 66, 0, 0, 0 ], "focus": [ null, null, null, "insert", null, null, null ], "placeholders": [ true, true, true, false, true, true, true ], "markers": [], "regions": [] } ] }, { "i": 28, "op": "lanes", "caption": "Place 75 at output[5] (digit 7).", "note": null, "codeLine": 4, "stats": { "pass": 2 }, "lanes": [ { "id": "arr", "label": "array", "array": [ 170, 90, 2, 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] } ] }