Created
February 12, 2021 19:33
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Build a suffix array from string
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| #!/usr/bin/env python3 | |
| import sys | |
| from operator import itemgetter | |
| input = sys.stdin.readline | |
| def insr(): | |
| s = input() | |
| return(list(s[:len(s) - 1])) | |
| def suffixArray(s): | |
| s += "$" | |
| n = len(s) | |
| if n == 0: | |
| return [] | |
| p = [0] * n | |
| c = [0] * n | |
| a = [0] * n | |
| for i in range(n): | |
| a[i] = (s[i], i) | |
| a.sort() | |
| for i in range(n): | |
| p[i] = a[i][1] | |
| c[p[0]] = 0 | |
| for i in range(1,n): | |
| if a[i][0] == a[i-1][0]: | |
| c[p[i]] = c[p[i-1]] | |
| else: | |
| c[p[i]] = c[p[i-1]] + 1 | |
| k = 0 | |
| while ((1<<k) < n): | |
| a = [None] * n | |
| for i in range(n): | |
| a[i] = ((c[i], c[(i+(1 << k)) % n]), i) | |
| a.sort() | |
| for i in range(n): | |
| p[i] = a[i][1] | |
| c[p[0]] = 0 | |
| for i in range(1,n): | |
| if a[i][0] == a[i-1][0]: | |
| c[p[i]] = c[p[i-1]] | |
| else: | |
| c[p[i]] = c[p[i-1]] + 1 | |
| k += 1 | |
| for c in p: | |
| print(c, end=' ') | |
| if __name__ == "__main__": | |
| s = insr() | |
| suffixArray(s) | |
| print() |
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