View Code of Problem 6

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main() {
	int t, n, i, j;
	scanf("%d", &t);
	while (t--) {
		scanf("%d", &n);
		int a[1000], b[1000];
		for (i = 0; i < n; i++) {
			scanf("%d %d", &a[i], &b[i]);
		}
		int max = 0;
		for (i = 0; i < n; i++) {
			if (b[i] - a[i] > max) {
				max = b[i] - a[i]; //确定最大步长
			}
		}
		int flag = 0;
		for (i = 0; i < n - 1; i++) {
			if (a[i + 1] - a[i] < max) {
				flag = 1;
				break;
			}
		}
		if (flag == 0) {
			printf("YES\n");
		} else {
			printf("NO\n");
		}
	}
	return 0;
}