B. OR in Matrix
Time Limit: 20 Sec
Memory Limit: 256 MB
题目连接
http://codeforces.com/contest/486/problem/B
Description
where is equal to 1 if some ai = 1, otherwise it is equal to 0.
Nam has a matrix A consisting of m rows and n columns. The rows are numbered from 1 to m, columns are numbered from 1 to n. Element at row i (1 ≤ i ≤ m) and column j (1 ≤ j ≤ n) is denoted as Aij. All elements of A are either 0 or 1. From matrix A, Nam creates another matrix B of the same size using formula:
.
(Bij is OR of all elements in row i and column j of matrix A)
Nam gives you matrix B and challenges you to guess matrix A. Although Nam is smart, he could probably make a mistake while calculating matrix B, since size of A can be large.
Input
The first line contains two integer m and n (1 ≤ m, n ≤ 100), number of rows and number of columns of matrices respectively.
The next m lines each contain n integers separated by spaces describing rows of matrix B (each element of B is either 0 or 1).
Output
In the first line, print "NO" if Nam has made a mistake when calculating B, otherwise print "YES". If the first line is "YES", then also print m rows consisting of n integers representing matrix A that can produce given matrix B. If there are several solutions print any one.
Sample Input
2 2
1 0
0 0
Sample Output
NO
HINT
题意
给你b矩阵,bij = ai1 | ai2 | ai3 ...... | aim | a1j | a2j ..... | anj
然后让你求a矩阵
题解:
找找规律就知道,如果bij是0,那么a矩阵中,第i行和第j行都是0
如果bij是1,那么a矩阵中,第i行或者第j行存在一个1就好了
代码
#include<stdio.h> #include<iostream> using namespace std; int a[110][110]; int vis1[110]; int vis2[110]; int main() { int n,m;scanf("%d%d",&n,&m); for(int i=1;i<=n;i++) for(int j=1;j<=m;j++) scanf("%d",&a[i][j]); for(int i=1;i<=n;i++) { for(int j=1;j<=m;j++) { if(a[i][j]==0) { vis1[i]=1; vis2[j]=1; } } } int sum1=0; for(int i=1;i<=n;i++) sum1+=vis1[i]; int sum2=0; for(int i=1;i<=m;i++) sum2+=vis2[i]; for(int i=1;i<=n;i++) { for(int j=1;j<=m;j++) { if(a[i][j]==1) { if(sum1==n||sum2==m) { printf("NO "); return 0; } if(vis1[i]&&vis2[j]) { printf("NO "); return 0; } } } } printf("YES "); for(int i=1;i<=n;i++) { for(int j=1;j<=m;j++) { if(vis1[i]||vis2[j]) { printf("0 "); } else printf("1 "); } printf(" "); } }