【dfs】HDU 4141

簡單的dfs，bfs也可以

int g[11][11];int n,m;bool vis[11][11];int d[4][2] = {0,1,0,-1,1,0,-1,0};int ans;void dfs(int x,int y){    if(vis[x][y])return ;    vis[x][y] = 1;    int i;    if(x==1 || y==1 || x==n || y==m)        ans++;    for(i=0;i<4;i++){        int xx = x+d[i][0];        int yy = y+d[i][1];        if(xx<1 || yy<1 || xx>n || yy>m)continue;        if(g[xx][yy]>=g[x][y]){            dfs(xx,yy);        }    }}int main(){    int t;    scanf("%d",&t);    int ca=1;    while(t--){        scanf("%d%d",&n,&m);        int i,j;        int s,t;        scanf("%d%d",&s,&t);        for(i=1;i<=n;i++){            for(j=1;j<=m;j++){                scanf("%d",&g[i][j]);                vis[i][j] = 0;            }        }        ans = 0;        dfs(s,t);        printf("Case #%d: %d\n",ca++,ans);    }    return 0;}