[OpenJudge-NOI]棋盘问题 回溯

代码

#include 
#include 
#include 
using namespace std;

char a[100][100];
int vis[100],ans,n,k;

int Backtrack(int cur,int num) {
    if(num>k){
        ans++;
        return 1;
    }else{
        for(int i=cur;ifor(int j=0;jif(a[i][j]=='#'&&vis[j]==0) {
                    vis[j]=1;
                    Backtrack(i+1,num+1);
                    vis[j]=0;
                }
            }
        }
    }
}
int main() {    
    while(scanf("%d%d",&n,&k)!=EOF) {
        memset(vis,0,sizeof(0));
        if(n==-1&&k==-1) break;
        for(int i=0;iscanf("%s",a[i]);
        }
        /*for(int i=0;i 
        ans=0;
        Backtrack(0,1);
        printf("%d\n",ans); 
    }
    return 0;
}