金孝渊综艺:浙大acm题库1002求助

是FireNet那个题么?
典型的DFS
这个是我的代码:

#include <iostream>
using namespace std;

bool canput(char map[5][5], int y, int x){
if(map[y][x] != '.')return 0;
int i;
for(i = y - 1; i >= 0; i--){
if(map[i][x] == 'X')break;
if(map[i][x] == 'F')return 0;
}
for(i = x - 1; i >= 0; i--){
if(map[y][i] == 'X')break;
if(map[y][i] == 'F')return 0;
}
return 1;
}

void dfs(char map[5][5], int n, int depth, int put, int &max){
if(put > max)max = put;

if(depth >= n*n)
return;

dfs(map,n,depth+1,put,max);

int y = depth / n, x = depth % n;

if(canput(map,y,x)){
map[y][x] = 'F';
put++;
dfs(map, n, depth+1, put, max);
map[y][x] = '.';
put--;
}
}

int main(){
//freopen("input.txt","r",stdin);
char map[5][5];
int i,n,firenet;
while(scanf("%d",&n)!=EOF && n){
firenet = 0;
for(i = 0; i < n; i++)scanf("%s",&map[i]);
dfs(map,n,0,0,firenet);
printf("%d\n",firenet);
}
return 0;
}

#include<stdio.h>
#define MAX 4
#define WALL -1
char map[MAX+2][MAX+2];
int size,max,cur,depth;
void test(){
int i =depth/size +1, j =depth%size +1,n;
if(depth>=size*size){
if(cur>max) max =cur;
return;
}
if(!map[i][j]){
map[i][j] =1;
for(n=i+1;map[n][j]!=WALL;n++) map[n][j]++;
for(n=i-1;map[n][j]!=WALL;n--) map[n][j]++;
for(n=j+1;map[i][n]!=WALL;n++) map[i][n]++;
for(n=j-1;map[i][n]!=WALL;n--) map[i][n]++;
depth++;
cur++;
test();
cur--;
depth--;
for(n=i+1;map[n][j]!=WALL;n++) map[n][j]--;
for(n=i-1;map[n][j]!=WALL;n--) map[n][j]--;
for(n=j+1;map[i][n]!=WALL;n++) map[i][n]--;
for(n=j-1;map[i][n]!=WALL;n--) map[i][n]--;
map[i][j] =0;
}
depth++;
test();
depth--;
}
int main(){
int i,j;
while(scanf("%d",&size)!=EOF&&size>0){
getchar();
for(i=0;i<=size+1;i++)
map[0][i] =map[size+1][i] =map[i][0] =map[i][size+1] =WALL;
for(i=1;i<=size;i++){
for(j=1;j<=size;j++) map[i][j] = (getchar()=='X')?WALL:0;
getchar();
}
max =cur =depth =0;
test();
printf("%d\n",max);
}
return 0;
}