USACO 3.3 Home on the Range(最大子矩阵问题）

/*
ID: cuizhe
LANG: C++
TASK: range
*/
#include <iostream>
#include <cstdio>
#include <cstring>
#include <cmath>
using namespace std;
#define N 501
char str

;
int key

,x

,y

;
int o
,map

;
int Min(int a,int b,int c)
{
int t = a;
if(t > b)
t = b;
if(t > c)
t = c;
return t;
}
int main()
{
int i,j,k,n;
freopen("range.in","r",stdin);
freopen("range.out","w",stdout);
scanf("%d",&n);
for(i = 1;i <= n;i ++)
scanf("%s",str[i]);
for(i = 1;i <= n;i ++)
{
for(j = 1;j <= n;j ++)
{
if(str[i][j-1] == '1')
map[i][j] = 1;
}
}
for(i = 1;i <= n;i ++)
{
for(j = 1;j <= n;j ++)
{
if(map[i][j] == 1)
{
x[i][j] = x[i-1][j]+1;
y[i][j] = y[i][j-1]+1;
if(map[i-1][j-1] == 1)
key[i][j] = Min(x[i][j],y[i][j],key[i-1][j-1]+1);
else
key[i][j] = 1;
}
else
{
x[i][j] = 0;
y[i][j] = 0;
key[i][j] = 0;
}
}
}
for(i = 1;i <= n;i ++)
{
for(j = 1;j <= n;j ++)
{
for(k = 2;k <= key[i][j];k ++)
{
o[k] ++;
}
}
}
for(i = 2;i <= n;i ++)
{
if(o[i])
printf("%d %d\n",i,o[i]);
}
return 0;
}