U521476 求联通块个数 求调

#include <iostream>
#include <vector>

using namespace std;
const int dx[] = {-1, 1, 0, 0}; 
const int dy[] = {0, 0, -1, 1};

void dfs(vector<vector<int>>& image, int x, int y, int n) {
    if(x < 0 || x >= n || y < 0 || y >= n || image[x][y] == 0) return;
    image[x][y] = 0; 
    for(int i = 0; i < 4; ++i) {
        int newX = x + dx[i];
        int newY = y + dy[i];
        dfs(image, newX, newY, n); 
    }
}

int main() {
    int n;
    cin >> n;
    vector<vector<int>> image(n, vector<int>(n));
    for(int i = 0; i < n; ++i) {
        for(int j = 0; j < n; ++j) {
            cin >> image[i][j];
        }
    }

    int count = 0;
    for(int i = 0; i < n; ++i) {
        for(int j = 0; j < n; ++j) {
            if(image[i][j] == 1) { 
                dfs(image, i, j, n); 
                count++; 
            }
        }
    }

    cout << count << endl;

    return 0;
}