P3120 [USACO15FEB]牛跳房子(金)Cow Hopscotch (Gold) 就像人类喜欢跳格子游戏一样,FJ的奶牛们发明了一种新的跳格子游戏.虽然这种接近一吨的笨拙的动物玩跳格子游戏几乎总是不愉快地结束,但是这并没有阻止奶牛们在每天下午参加跳格子游戏 游戏在一个R×C的网格上进行,每个格子有一个取值在1-k之间的整数标号,奶牛开始在左上角的格子,目的是通过若干次跳跃后到达右下角的格子,当且仅当格子A和格子B满足如下条件时能从格子A跳到格子B: 1.B格子在A格子的严格右方(B的列…

题意 题目链接 Sol \(f[i][j]\)表示前\(i\)行\(j\)列的贡献,转移的时候枚举从哪里转移而来,复杂度\(O(n^4)\) 然后考虑每一行的贡献,动态开节点线段树维护一下每种颜色的答案 转移的时候用总的方案减去相同颜色的方案 复杂度\(O(n^2 log^2 n)\) #include<bits/stdc++.h> #define LL long long using namespace std; const int MAXN = 1001, INF = 1e9 + 10,…

题目描述 Just like humans enjoy playing the game of Hopscotch, Farmer John&apos;s cows have invented a variant of the game for themselves to play. Being played by clumsy animals weighing nearly a ton, Cow Hopscotch almost always ends in disaster, but thi…

P3080 [USACO13MAR]牛跑The Cow Run 题目描述 Farmer John has forgotten to repair a hole in the fence on his farm, and his N cows (1 <= N <= 1,000) have escaped and gone on a rampage! Each minute a cow is outside the fence, she causes one dollar worth of dam…

P2853 [USACO06DEC]牛的野餐Cow Picnic 题目描述 The cows are having a picnic! Each of Farmer John's K (1 ≤ K ≤ 100) cows is grazing in one of N (1 ≤ N ≤ 1,000) pastures, conveniently numbered 1...N. The pastures are connected by M (1 ≤ M ≤ 10,000) one-way path…

P2853 [USACO06DEC]牛的野餐Cow Picnic 题目描述 The cows are having a picnic! Each of Farmer John's K (1 ≤ K ≤ 100) cows is grazing in one of N (1 ≤ N ≤ 1,000) pastures, conveniently numbered 1...N. The pastures are connected by M (1 ≤ M ≤ 10,000) one-way path…

题目传送门 这是一道典型的记忆化搜索题. f[x][y]表示以x,y为右下角的方案数. code: #include <cstdio> #define mod 1000000007 using namespace std; ][],f[][]; int DP(int x,int y){ if(f[x][y])return f[x][y]; ;i<x;i++) ;j<y;j++) if(a[i][j]!=a[x][y])f[x][y]+=DP(i,j),f[x][y]%=mod; r…

题目描述 The cows are having a picnic! Each of Farmer John's K (1 ≤ K ≤ 100) cows is grazing in one of N (1 ≤ N ≤ 1,000) pastures, conveniently numbered 1...N. The pastures are connected by M (1 ≤ M ≤ 10,000) one-way paths (no path connects a pasture to…

https://www.luogu.org/problem/show?pid=3029 题目描述 Farmer John has hired a professional photographer to take a picture of some of his cows. Since FJ's cows represent a variety of different breeds, he would like the photo to contain at least one cow fro…

题目描述 Like everyone else, FJ is always thinking up ways to increase his revenue. To this end, he has set up a series of tolls that the cows will pay when they traverse the cowpaths throughout the farm. The cows move from any of the N (1 <= N <= 250)…