Oil Deposits DFS FloodFill漫水填充法求连通块问题

#include<stdio.h>

char a[105][105];
int c,n,m;
void dfs(int x,int y){
    if(x<0||y<0||x>=n||y>=m) return;
    if(a[x][y]==‘*‘) return;
    if(a[x][y]==‘@‘){
        a[x][y]=‘*‘;
        dfs(x+1,y);
        dfs(x+1,y+1);
        dfs(x,y+1);
        dfs(x-1,y+1);
        dfs(x-1,y);
        dfs(x-1,y-1);
        dfs(x,y-1);
        dfs(x+1,y-1);
    }
}
int main()
{
    int i,j;
    while(scanf("%d%d",&n,&m)&&!(n==0&&m==0)){
        c=0;
    for(i=0;i<n;i++){
        getchar();
        scanf("%s",a[i]);
    }
    for(i=0;i<n;i++){
        for(j=0;j<m;j++){
            if(a[i][j]==‘@‘){
                c++;
                dfs(i,j);
            }
        }
    }
    printf("%d\n",c);
    }
    return 0;
}