codeforces 325A. Square and Rectangles

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <math.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <vector>
#include <string>
#include <iostream>
#include <algorithm>
using namespace std;
#define ll long long
#define ls rt<<1
#define rs ls1
#define lson l,mid,ls
#define rson mid+1,r,rs
#define middle (l+r)>>1
#define eps (1e-9)
#define clr_all(x,c) memset(x,c,sizeof(x))
#define clr(x,c,n) memset(x,c,sizeof(x[0])*(n+1))
#define MOD 1000000007
#define inf 100000007
#define pi acos(-1.0)
#define M 200000+5
int a[6][5];
int getarea(int x1,int x2,int y1,int y2){
int x,y;
x=x2-x1;y=y2-y1;
return x*y;
}
int main(){
    int mx1,mx2,my1,my2,i,j,suma,n,x,y;
    while(~scanf("%d",&n)){
mx1=M,mx2=0;
my1=M,my2=0;
suma=0;
for(i=0;i<n;i++){
scanf("%d %d %d %d",&a[i][0],&a[i][1],&a[i][2],&a[i][3]);
if(a[i][0]>a[i][2]){
j=a[i][0];
a[i][0]=a[i][2];
a[i][2]=j;
}
if(a[i][1]>a[i][3]){
j=a[i][1];
a[i][1]=a[i][3];
a[i][3]=j;
}
if(mx1>a[i][0])mx1=a[i][0];
if(my1>a[i][1])my1=a[i][1];
if(mx2<a[i][2])mx2=a[i][2];
if(my2<a[i][3])my2=a[i][3];
suma+=getarea(a[i][0],a[i][2],a[i][1],a[i][3]);
}
x=mx2-mx1;y=my2-my1;
j=x*y;
if(suma==j&&x==y)puts("YES");
else puts("NO");
}
    return 0;
}