BFS——求矩阵中“块”的个数

#include<stdio.h>
#include<queue>
using namespace std;
const int maxn = 100;
struct node{
    
    
	int x, y;
}Node;

int n, m;              
int matrix[maxn][maxn];   // 01矩阵 
bool inq[maxn][maxn] = {
    
    false};
int X[4] = {
    
    0, 0, 1, -1};
int Y[4] = {
    
    1, -1, 0, 0}; // 增量数组

bool judge(int x, int y)
{
    
    
    if(x >= n || x < 0 || y >= m || y < 0) return false;
	if(matrix[x][y] == 0 || inq[x][y] == true) return false;
	return true;	
} 

void BFS(int x, int y)
{
    
    
	queue<node> Q;
	Node.x = x, Node.y = y;
	Q.push(Node);
	inq[x][y] = true;
	while(!Q.empty())
	{
    
    
		node top = Q.front();
		Q.pop();
		for(int i = 0; i < 4; i++)
		{
    
    
			int newX = top.x + X[i];
			int newY = top.y + Y[i];
			if(judge(newX, newY))
			{
    
    
				Node.x = newX;
				Node.y = newY;
				Q.push(Node);
				inq[newX][newY] = true;
			}
		}
	}
}

int main()
{
    
    
	scanf("%d%d", &n, &m);
	for(int x = 0; x < n; x++)
	{
    
    
		for(int y = 0; y < m; y++)
		{
    
    
			scanf("%d", &matrix[x][y]);
		}
	}
	int ans = 0;
	for(int x = 0; x < n; x++)
	{
    
    
		for(int y = 0; y < m; y++)
		{
    
    
			if(matrix[x][y] == 1 && inq[x][y] == false)
			{
    
    
				ans++;
				BFS(x, y);
			}
		}
	}
	printf("%d", ans);
	return 0;
}