0 or 1 题目链接: Rhttp://acm.hust.edu.cn/vjudge/contest/122685#problem/R Description Given a n*n matrix C ij (1<=i,j<=n),We want to find a n*n matrix X ij (1<=i,j<=n),which is 0 or 1. Besides,X ij meets the following conditions: 1.X 12+X 13+...X 1…

0 or 1 Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 2811    Accepted Submission(s): 914 Problem Description Given a n*n matrix Cij (1<=i,j<=n),We want to find a n*n matrix Xij (1<=i,j<…

HDU - 4370 参考:https://www.cnblogs.com/hollowstory/p/5670128.html 题意: 给定一个矩阵C, 构造一个A矩阵,满足条件: 1.X12+X13+...X1n=1 2.X1n+X2n+...Xn-1n=1 3.for each i (1<i<n), satisfies ∑Xki (1<=k<=n)=∑Xij (1<=j<=n). 使得∑Cij*Xij(1<=i,j<=n)最小. 思路: 理解条件之前先…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4370 题目大意:有一个n*n的矩阵Cij(1<=i,j<=n),要找到矩阵Xij(i<=1,j<=n)满足以下条件: 1.X 12+X 13+...X 1n=1  2.X 1n+X 2n+...X n-1n=1  3.for each i (1<i<n), satisfies ∑X ki (1<=k<=n)=∑X ij (1<=j<=n). 举个例子…

[题目链接](http://acm.hdu.edu.cn/showproblem.ph Problem Description Given a n/n matrix Cij (1<=i,j<=n),We want to find a n/n matrix Xij (1<=i,j<=n),which is 0 or 1. Besides,Xij meets the following conditions: 1.X12+X13+...X1n=1 2.X1n+X2n+...Xn-1n=…

题目传送门 题意:题目巨晦涩的传递出1点和n点的初度等于入度等于1, 其余点出度和入度相等 分析:求最小和可以转换成求最短路,这样符合条件,但是还有一种情况.1点形成一个环,n点也形成一个环,这样也是可以的,这样SPFA要稍微修改点,d[s] = INF,表示可以更新. #include <bits/stdc++.h> using namespace std; const int N = 3e2 + 5; const int INF = 0x3f3f3f3f; int w[N][N]; int…

出题人真是脑洞堪比黑洞 (然后自己也被吸进去了 理解一遍题意 三个条件可以转化为 1的出度是1, n的入度是1, 2~n-1的出度等于入度 不难发现1-n的最短路符合题意 然而其实还有另一种情况 1为起止点的最短闭环+n为起止点的最短闭环同样满足要求 因此取两者的min作为结果 #include <iostream> #include <string> #include <cstdio> #include <cmath> #include <cstri…

Description Given a n*n matrix C ij (1<=i,j<=n),We want to find a n*n matrix X ij (1<=i,j<=n),which is 0 or 1. Besides,X ij meets the following conditions: 1.X 12+X 13+...X 1n=1 2.X 1n+X 2n+...X n-1n=1 3.for each i (1<i<n), satisfies ∑X…

这个题说实话我没看出来,我看的别人的博客 https://blog.csdn.net/u013761036/article/details/39377499 这个人讲的很清楚,可以直接去看他的 题目给的 3个要求: 1.X 12+X 13+...X 1n=1 2.X 1n+X 2n+...X n-1n=1 3.for each i (1<i<n), satisfies ∑X ki (1<=k<=n)=∑X ij (1<=j<=n). 简单来说就是创建n个点,X 12+X…

<题目链接> 题目大意: 一个n*n的01矩阵,满足以下条件 1.X12+X13+...X1n=12.X1n+X2n+...Xn-1n=13.for each i (1<i<n), satisfies ∑Xki (1<=k<=n)=∑Xij (1<=j<=n). 另给出一个矩阵C,求∑Cij*Xij(1<=i,j<=n)的最小值. 解题分析: 显然,题目给的是一个0/1规划模型. 解题的关键在于如何看出这个模型的本质. 3个条件明显在刻画未知数之…