zoukankan      html  css  js  c++  java
  • 【洛谷 P1659】 [国家集训队]拉拉队排练(manacher)

    题目链接
    马拉车+简单膜你

    #include <cstdio>
    #include <cstring>
    #include <algorithm>
    using namespace std;
    const int MAXN = 11000010;
    const int MOD = 19930726;
    char b[MAXN], a[MAXN << 1];
    int hw[MAXN << 1], ans = 1, n, c[MAXN];
    #define ll long long
    ll now, m;
    int fast_pow(int a, ll k){
        int ans = 1;
        while(k){
           if(k & 1) ans = (ll)ans * a % MOD;
           a = (ll) a * a % MOD;
           k >>= 1;
        }
        return ans;
    }
    int main(){
        scanf("%d%lld", &n, &m);
        scanf("%s", b);
        a[0] = a[1] = '#';
        for(int i = 0; i < n; ++i)
           a[(i << 1) + 2] = b[i], a[(i << 1) + 3] = '#';
        int maxright = 0, mid; n = (n << 1) + 3;
        for(int i = 1; i < n; ++i){
           if(i < maxright)
             hw[i] = min(hw[(mid << 1) - i], hw[mid] + mid - i);
           else hw[i] = 1;
           while(a[i + hw[i]] == a[i - hw[i]]) ++hw[i];
           if(hw[i] + i > maxright){
             maxright = hw[i] + i;
             mid = i;
           }
           ++c[hw[i] - 1];
        }
        for(int i = (n - 3) >> 1; i; --i){
            if(i & 1 ^ 1) continue;
            now += c[i];
            if(m <= now){ ans = (ll) ans * fast_pow(i, m) % MOD; m = 0; break; }
            m -= now; ans = (ll) ans * fast_pow(i, now) % MOD;
        }
        if(m) ans = -1;
        printf("%d
    ", ans);
        return 0;
    }
    
    
  • 相关阅读:
    VTK二维图像的三维显示
    VtkTransform 和 SetPosition的区别
    Qt QList 遍历元素
    Qt QList详解
    QT QList介绍及应用
    Qt 生成随机区间浮点数 generateRand
    Qt qsrand qrand 产生随机数的两只方法
    Qt QStringLiteral
    Qt QMap简单用法
    Qt 遍历QMap
  • 原文地址:https://www.cnblogs.com/Qihoo360/p/10848541.html
Copyright © 2011-2022 走看看