Submission #530296

#	Time	Username	Problem	Language	Result	Execution time	Memory
530296		yungyao	Sandcastle 2 (JOI22_ho_t5)	C++17	9 / 100	5 ms	868 KiB

Main

using namespace std;
#include <iostream>
#include <algorithm>
#include <utility>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>

typedef long long LL;
typedef pair<int,int> pii;
#define pb push_back
#define mkp make_pair
#define F first
#define S second
#define iter(x) x.begin(),x.end()
#define REP(n) for (int __=n;__--;)
#define REP0(i,n) for (int i=0;i<n;++i)
#define REP1(i,n) for (int i=1;i<=n;++i)

const int maxn = 5e4+10, mod = 0;
const LL inf = 0;

void solve(){
	int n, m;
	int arr[maxn]{};

	cin >> n >> m;
	REP1(i, m) cin >> arr[i];
	LL cnt = 0, ans = m; bool up = true;
	REP1(i, m){
		if ((arr[i] > arr[i-1]) ^ up){
			ans += cnt * (cnt-1) / 2;
			cnt = 2;
			up = !up;
		}
		else ++cnt;
	}
	cout << ans + cnt * (cnt - 1) / 2;
}

int main(){
	ios_base::sync_with_stdio(false); cin.tie(0);

	solve();

	return 0;
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 10
• Subtask 3: 0 / 5
• Subtask 4: 0 / 56
• Subtask 5: 0 / 20