zoj 3672 Gao The Sequence

#include <stdio.h>#define LL long longint main(){ LL mx; LL sum; int n; LL a,b; while(scanf("%d", &n) != EOF){ mx = 0; sum = 0; for(int i = 0 ; i < n; i++){ scanf("%lld %lld", &a, &b); sum += a - b; if(mx < (a - b)) mx = a - b; } sum -= mx; if(sum >= mx && (sum + mx) % 2 == 0) printf("YESn"); else printf("NOn"); } return 0;}