CSP题解|201604-1 折点计数|100分

#include <bits/stdc++.h>
using namespace std;

int main() {
	int n,temp,res=0;
	cin>>n;
	vector<int>v;
	while(n--){
		cin>>temp;
		v.push_back(temp);
	}
	for(int i =1;i<v.size()-1;i++){
		if((v[i]>v[i-1] && v[i]>v[i+1])||(v[i]<v[i-1] && v[i]<v[i+1]))res++;
	}
	cout<<res<<endl;
}