UVA-806 Spatial Structures （四分树）

# include<iostream>
# include<cstdio>
# include<vector>
# include<string>
# include<cstring>
# include<algorithm>
using namespace std;

char p[80][80];
int ans;
vector<int>v;

int get(int r,int c,int w)
{
int cnt=0;
for(int i=r;i<r+w;++i)
for(int j=c;j<c+w;++j)
if(p[i][j]=='1')
++cnt;
return cnt;
}

int getVal(string path)
{
int l=path.size();
int res=0;
for(int i=l-1;i>=0;--i)
res=res*5+path[i]-'0';
return res;
}

///查看以(r,c)为左上角，边长为w的子正方形。下同。
void f1(int r,int c,int w,string path)
{
int k=get(r,c,w);
if(k==0)
return ;
if(k==w*w){
++ans;
v.push_back(getVal(path));
return ;
}
f1(r,c,w/2,path+'1');
f1(r,c+w/2,w/2,path+'2');
f1(r+w/2,c,w/2,path+'3');
f1(r+w/2,c+w/2,w/2,path+'4');
}

void f2(int r,int c,int w,int s)
{
if(s==0){
for(int i=r;i<r+w;++i)
for(int j=c;j<c+w;++j)
p[i][j]='*';
return ;
}
int mod=s%5;
if(mod==1)
f2(r,c,w/2,s/5);
else if(mod==2)
f2(r,c+w/2,w/2,s/5);
else if(mod==3)
f2(r+w/2,c,w/2,s/5);
else if(mod==4)
f2(r+w/2,c+w/2,w/2,s/5);
}

int main()
{
//freopen("UVA-806 Spatial Structures.txt","r",stdin);
int n,cas=0,flag=0;
while(scanf("%d",&n)&&n)
{
v.clear();
if(flag)
printf("\n");
flag=1;
if(n>0){
for(int i=0;i<n;++i)
scanf("%s",p[i]);
printf("Image %d\n",++cas);
ans=0;
f1(0,0,n,"");
sort(v.begin(),v.end());
int l=v.size();
for(int i=0;i<l;++i)
printf("%d%c",v[i],(i%12==11||i==l-1)?'\n':' ');
printf("Total number of black nodes = %d\n",ans);
}
if(n<0){
n=-n;
for(int i=0;i<n;++i){
for(int j=0;j<n;++j)
p[i][j]='.';
p[i]
=0;
}
int a;
while(scanf("%d",&a)&&a!=-1)
v.push_back(a);
printf("Image %d\n",++cas);
int l=v.size();
for(int i=0;i<l;++i)
f2(0,0,n,v[i]);
for(int i=0;i<n;++i)
puts(p[i]);
}
}
return 0;
}