UVa 352 - The Seasonal War ( DFS求连通块 )

思路

基础DFS
和油田那题思路一毛一样

AC代码

#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

char s[30][30];
int n;

void dfs( int x, int y ){
    s[x][y] = '0';
    for( int dx = -1; dx <= 1; dx++ ){
        for( int dy = -1; dy <= 1; dy++ ){
            int nx = x + dx, ny = y + dy;
            if( nx >= 0 && nx < n && ny >= 0 && ny < n && s[nx][ny] == '1' )
                dfs(nx, ny);
        }
    }
    return;
}

int solve(){
    int num = 0;
    for( int i = 0; i < n; i++ )
        for( int j = 0; j < n; j++ )
            if( s[i][j] == '1' ){
                dfs(i,j);
                num++;
            }
    return num;
}

int main()
{
    int eg, num = 0;
    while( ~scanf("%d",&n) ){
        memset(s,0,sizeof(s));
        for( int i = 0; i < n; i++ )
            scanf("%s",s[i]);
        eg = solve();
        printf("Image number %d contains %d war eagles.\n",++num, eg);
    }
    return 0;
}