[hdu7023]Yet Another Matrix Problem】的更多相关文章

关于$f(x)$的条件,将$C=A\times B$代入,即$\sum_{i=1}^{n}\sum_{j=1}^{n}\sum_{k=1}^{r}A_{i,k}B_{k,j}=x$ 调换枚举顺序,即$\sum_{k=1}^{r}(\sum_{i=1}^{n}A_{i,k})(\sum_{j=1}^{n}B_{k,j})=x$ 显然每一部分的值都是独立的,因此令$G_{x}$​​为$(\sum_{i=1}^{n}A_{i,k})(\sum_{j=1}^{n}B_{k,j})=x$​​的方案数,枚举…
THE MATRIX PROBLEM Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 41 Accepted Submission(s): 14   Problem Description You have been given a matrix CN*M, each element E of CN*M is positive and no…
THE MATRIX PROBLEM Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 8693    Accepted Submission(s): 2246 Problem Description You have been given a matrix CN*M, each element E of CN*M is positive…
THE MATRIX PROBLEM Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 5437    Accepted Submission(s): 1372 Problem Description You have been given a matrix CN*M, each element E of CN*M is positive…
THE MATRIX PROBLEM Time Limit: 4000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 7819    Accepted Submission(s): 2019 Problem Description You have been given a matrix CN*M, each element E of CN*M is positive…
You have been given a matrix C N*M, each element E of C N*M is positive and no more than 1000, The problem is that if there exist N numbers a1, a2, … an and M numbers b1, b2, …, bm, which satisfies that each elements in row-i multiplied with ai and e…
You have been given a matrix C N*M, each element E of C N*M is positive and no more than 1000, The problem is that if there exist N numbers a1, a2, - an and M numbers b1, b2, -, bm, which satisfies that each elements in row-i multiplied with ai and e…
题目链接:https://cn.vjudge.net/contest/276233#problem/H 题目大意:对于给定的矩阵  每一行除以ai  每一列除以bi 之后 数组的所有元素都还在那个L-R范围之内,a[i]和b[j]是不知道的,然后问你是否有这样的数组a和数组b满足条件. 具体思路:我们可以写出这样的等式, L<=Map[i][j]*a[i]/b[j]<=R, 然后继续化简 L/Map[i][j]<=a[i]/b[j]<=R/Map[i][j], 然后两边同时取log…
题意: 给一个n*m矩阵,每个格子上有一个数字a[i][j],给定L和U,问:是否有这样两个序列{a1...an}和{b1...bn},满足 L<=a[i][j]*ai/bj<=U .若存在输出yes,否则no. 思路: 能够得到的是一堆不等式,那么可以用最短路来解决差分约束系统.但是a[i][j]*ai/bj<=U是除的,得提前变成减的才行.可以用对数log来解决,先不管a[i][j],logai-logbj<=U不就行了?可以得到: (1)logai - logbj<=U…
题意:给定一个最大400*400的矩阵,每次操作可以将某一行或某一列乘上一个数,问能否通过这样的操作使得矩阵内的每个数都在[L,R]的区间内. 析:再把题意说明白一点就是是否存在ai,bj,使得l<=cij*(ai/bj)<=u (1<=i<=n,1<=j<=m)成立. 首先把cij先除到两边去,就变成了l'<=ai/bj<=u',由于差分约束要是的减,怎么变成减法呢?取对数呗,两边取对数得到log(l')<=log(ai)-log(bj)<=l…