代码

#include<bits/stdc++.h>
#define int long long 
#define N 500005
using namespace std;
int n , ans = 0 , len;
int a[N];
int dfs(int st,int sum){
	if(st==len)return sum;
	if(a[st+1]<a[st])dfs(st+1,sum+1);
}
signed main(){
    scanf("%d",&n);
    for(int i = 1;i <= n;i++){
    	scanf("%d",&a[i]);
	}
	len = unique(a+1,a+1+n) - (a+1);
	for(int i = 1;i <= n;i++){
		a[i] = lower_bound(a+1,a+1+len,a[i])-a;
	}
	for(int i = 1;i < n;i++){
		ans += dfs(a[i],0);
	}
	printf("%d",ans);
    return 0;
}