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public static void sort( int[] a) { int i, m = a[0], exp = 1, n = a.length; int[] b = new int[10]; for (i = 1; i < n; i++) if (a[i] > m) m = a[i]; while (m / exp > 0) { int[] bucket = new int[10];

for (i = 0; i < n; i++) bucket[(a[i] / exp) % 10]++; for (i = 1; i < 10; i++) bucket[i] += bucket[i - 1]; for (i = n - 1; i >= 0; i--) b[--bucket[(a[i] / exp) % 10]] = a[i]; for (i = 0; i < n; i++) a[i] = b[i]; exp *= 10; } }