#include <iostream> using namespace std; int main() { int a[15][15]={0},i,j,n,m,b; cin>>n>>m; for(i=0;i<n;i++){ for(j=0;j<m;j++){ cin>>a[i][j]; } } for(i=0;i<n;i++){ for(j=0;j<m;j++){ if(a[i][j]!=0&&a[i][j]!=1){ cout<<"No"; return 0; } } } cout<<"Yes"; return 0; } /************************************************************** Problem: 1828 User: wangyiyang Language: C++ Result: Accepted Time:22 ms Memory:2072 kb ****************************************************************/