AcWing 600. 仰视奶牛 单调栈模板题

https://www.acwing.com/problem/content/description/602/

找x右边第一个大于x的数的位置

const int N = 1e5 + 10,T = 20;

int n;
LL a[N],stk[N],top,r[N];


void solve()
{
	cin >> n;
	for (int i = 1;i <= n;i ++) cin >> a[i];
	
	for (int i = n;i >= 1;i --)
	{
		while(top && a[stk[top]] <= a[i]) top--;
		if (top) r[i] = stk[top];
		else r[i] = 0;
		stk[++top] = i;
	}	
	
	for (int i = 1;i <= n;i ++)
		cout << r[i] << endl;
}