【模板】后缀数组

 1 #include <algorithm>
 2 #include <iostream>
 3 #include <cstring>
 4 #include <cstdlib>
 5 #include <cstdio>
 6 
 7 using namespace std;
 8 
 9 const int N = 1001010;
10 
11 char s[N];
12 int n, m, c[N], y[N], x[N], sa[N], rk[N];
13 
14 inline void Get_SA()
15 {
16     for (int i = 1; i <= n; ++i) ++c[x[i] = s[i]];
17     for (int i = 2; i <= m; ++i) c[i] += c[i - 1];
18     for (int i = n; i >= 1; --i) sa[c[x[i]]--] = i;
19     for (int k = 1; k <= n; k <<= 1)
20     {
21         int num = 0;
22         for (int i = n - k + 1; i <= n; ++i) y[++num] = i;
23         for (int i = 1; i <= n; ++i) if (sa[i] > k) y[++num] = sa[i] - k;
24         for (int i = 1; i <= m; ++i) c[i] = 0;
25         for (int i = 1; i <= n; ++i) ++c[x[i]];
26         for (int i = 2; i <= m; ++i) c[i] += c[i - 1];
27         for (int i = n; i >= 1; --i) sa[c[x[y[i]]]--] = y[i], y[i] = 0;
28         swap(x, y);
29         x[sa[1]] = 1, num = 1;
30         for (int i = 2; i <= n; ++i) 
31             x[sa[i]] = (y[sa[i]] == y[sa[i - 1]] && 
32             y[sa[i] + k] == y[sa[i - 1] + k]) ? num : ++num;
33         if (num == n) break;
34         m = num;
35     }
36     for (int i = 1; i <= n; ++i)
37         printf("%d ", sa[i]);
38 }
39 
40 int main()
41 {
42     scanf("%s", s + 1);
43     n = strlen(s + 1), m = 123;
44     Get_SA();
45     return 0;
46 }