uva 514 - Rails(栈)

#include <cstdio>
#include <cstring>
#include <algorithm>

using namespace std;
const int maxn = 1005;

int N, arr[maxn];

bool judge () {
for (int i = 1; i < N - 1; i++) {
if (arr[i-1] > arr[i+1] && arr[i+1] > arr[i])
return false;
}
return true;
}

int main () {
while (scanf("%d", &N) == 1 && N) {
while (scanf("%d", &arr[0]) && arr[0]) {
for (int i = 1; i < N; i++)
scanf("%d", &arr[i]);
printf("%s\n", judge() ? "Yes" : "No");
}
printf("\n");
}
return 0;
}