View Code of Problem 490

#include<stdio.h>
int main()
{
	int a[1000];
	int n;
	int flag1=0;
	while(scanf("%d",&n)!=EOF&&n!=0)
	{
		
		while(scanf("%d",&a[0]),a[0])
		{
			int flag=1;
			if(flag1==1)
				printf("\n");
			flag1==2;
			for(int i=1;i<n;i++)
             scanf("%d",&a[i]);
			for(int i=1;i<n-1;i++)
			    if((a[i]<a[i-1])&&(a[i]<a[i+1])&&(a[i-1]>a[i+1]))
				{
					flag=0;
					break;
				}
			if(flag)
				printf("Yes\n");
			else  
				printf("No\n");
			flag1=2;
		}

	}
}