I did the first question and saw the previous release. I found that the same method is the same. 4x4 has not changed. I just added an output conversion path. I didn’t set zero to one. I wrote a big simulation directly and recorded it after flipping it. The number of steps is recorded, wonderful, and I have a little more understanding of recursion.
Write it again tomorrow, come on.
#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
char str[5][5];
int ansx[20],ansy[20];
int tx[20],ty[20];
int ans=50;
bool check(){
for(int i=0;i<4;i++){
for(int j=0;j<4;j++){
if(str[i][j]!='-') return 0;
}
}
return 1;
}
void change(int x){
int xx=x/4;
int yy=x%4;
for(int i=0;i<4;i++){
if(str[i][yy]=='-') str[i][yy]='+';
else str[i][yy]='-';
if(str[xx][i]=='-') str[xx][i]='+';
else str[xx][i]='-';
}
if(str[xx][yy]=='-') str[xx][yy]='+';
else str[xx][yy]='-';
}
void dfs(int x,int step){
if(check()){
if(step<ans){
ans=step;
for(int i=1;i<=ans;i++){
ansx[i]=tx[i];
ansy[i]=ty[i];
}
}
return ;
}
if(x>=16) return ;
dfs(x+1,step);
change(x);
tx[step+1]=x/4+1;
ty[step+1]=x%4+1;
dfs(x+1,step+1);
change(x);
}
int main(){
for(int i=0;i<4;i++){
scanf("%s",str[i]);
}
dfs(0,0);
printf("%d\n",ans);
for(int i=1;i<=ans;i++){
printf("%d% d\n",ansx[i],ansy[i]);
}
return 0;
}