蓝桥杯 历届试题 剪格子 简单的DFS~~注意输入有陷阱~~

#include <cstdio>
#include <queue>
#include <algorithm>
#include <climits>
#include <cstring>
using namespace std ;

int ans = INT_MAX ;
const int dir[4][2] = {{1,0},{-1,0},{0,-1},{0,1}} ; 
int map[15][15] , sum = 0;
bool visited[15][15] ;
int row,col ;
bool judge(int x , int y)
{
	if(x<0||y<0||x>=row||y>=col)
	{
		return false ;
	}
	return true ;
}

void DFS(int x , int y , int add , int count)
{
	if(add == sum/2)
	{
		if(count<ans)
		{
			ans = count ;
		}
		return ;
	}
	for(int i = 0 ; i < 4 ; ++i)
	{
		int nextX = x + dir[i][0] , nextY = y + dir[i][1] ;
		if(!judge(nextX,nextY))
		{
			continue ;
		}
		if(!visited[nextX][nextY]&&add+map[nextX][nextY]<=sum/2)
		{
			visited[nextX][nextY] = true ;
			DFS(nextX,nextY,add+map[nextX][nextY],count+1) ;
			visited[nextX][nextY] = false ;
		}
	}
}

int main()
{
	while(scanf("%d%d",&col,&row) != EOF)
	{
		sum = 0 ;
		for(int i = 0 ; i < row ; ++i)
		{
			for(int j = 0 ; j < col ; ++j)
			{
				scanf("%d",&map[i][j]) ;
				sum += map[i][j] ;
			}
		}
		if(sum%2 == 1)
		{
			printf("0\n") ;
			continue ;
		}
		memset(visited,false,sizeof(visited)) ;
		ans = INT_MAX ;
		DFS(0,0,map[0][0],1) ;
		if(ans == INT_MAX)
			printf("0\n") ;
		else
			printf("%d\n",ans) ;
	}
	return 0 ;
}