View Code of Problem 6

#include<stdio.h>
int main(){
  int T;
  int n,l,r,i,flag;
  scanf("%d",&T);
  while(T--){
    scanf("%d",&n);
    for(i=0;i<n;i++){
    	  scanf("%d",&l);
    	  scanf("%d",&r);
          if(r-l==1){
            flag=1;
          }else{flag=0;}
      flag++;
    }
    if(flag==n){
      printf("YES");}
    else{printf("NO");}
  }
 return 0; 
}