//入力チェック
#include<stdio.h>
#include<assert.h>
#include<string.h>
char s[1010];
int main(){
	int n;
	assert(scanf("%d\n",&n)==1);
	assert(1<=n&&n<=100000);
	for(int i=0;i<n;i++){
		assert(fgets(s,1000,stdin));
		int a,b;
		assert(sscanf(s,"%d %d",&a,&b)==2);
		assert(1<=a&&a<=1000000000);
		assert(1<=b&&b<=1000000000);
	}
	assert(scanf("%s",s)==-1);
}