后缀数组模板

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劳资终于搞懂后缀数组啦！！！

#include "cstdio"inline int readStr( char* s )  {    static int len;    static char ch;    len = 0;    while((ch = (char) getchar()) == ' ' || ch == '\n');    do s[len++] = ch; while((ch = (char) getchar()) != ' ' && (ch ^ 10) && (ch ^ -1));    return len;}#define P 20#define MAXN 100005#define min(a, b)  ((a) < (b) ? (a) : (b))typedef class Suffix_Array  {private:    short flag = 0;    int n, a[MAXN], b[MAXN], c[MAXN], sa[MAXN], height[MAXN], rank[MAXN], log2[MAXN], st[MAXN][P];    inline void Rmq_Init(int* a, int n)  {        for(register int i = 2; i <= n; ++i)    log2[i] = log2[i >> 1] + 1;        for(register int i = 0; i <= n; ++i)    st[i][0] = a[i];        for(register int i, j = 1, len; j <= log2[n]; ++j)            for(i = 0, len = (1 << j); i + len - 1 <= n; ++i)                st[i][j] = min(st[i + (len >> 1)][j - 1], st[i][j - 1]);    }    inline int Ask_Rmq(int l, int r)  {        static int k;        if(l > r)   {   l ^= r ^= l ^= r;  }        k = log2[r - l + 1];        return min(st[l][k], st[r - (1 << k) + 1][k]);    }public:    void build(char* s, int n, int m)  {        int *x = a, *y = b, *t;  this -> n = n;        for(register int i = 0; i < m; c[i++] = 0);        for(register int i = 0; i < n; ++c[x[i] = s[i++]]);             for(register int i = 1; i < m; ++i) c[i] += c[i - 1];        for(register int i = n - 1; ~i; sa[--c[x[i]]] = i--);        for(register int i, k = 1, p = 1; p < n && k <= n; k <<= 1, m = p)  {            for(p = 0, i = n - k; i < n; y[p++] = i++);            for(i = 0; i < n; sa[i] >= k ? y[p++] = sa[i++] - k : ++i);            for(i = 0; i < m; c[i++] = 0);            for(i = 0; i < n; ++c[x[y[i++]]]);            for(i = 1; i < m; ++i)  c[i] += c[i - 1];            for(i = n - 1; ~i; sa[--c[x[y[i]]]] = y[i--]);            for(t = x, x = y, y = t, p = 1, x[sa[0]] = 0, i = 1; i < n; ++i)                x[sa[i]] = (y[sa[i - 1]] == y[sa[i]] && y[sa[i - 1] + k] == y[sa[i] + k]) ? p - 1 : p++;        }        for(register int i = 0; i < n; rank[sa[i]] = i++);        for(register int i = 0, k = 1, j; i < n; height[rank[i++]] = k)            for(--k, j = sa[rank[i] - 1]; s[i + k] == s[j + k]; ++k);    }    inline int Lcp(int l, int r)  {        if( !flag )  {  Rmq_Init(height, n); flag = 1; }        return Ask_Rmq(rank[l] + 1, rank[r]);    }} Suffix;char s[MAXN];Suffix Sa;int main()  {}