Submission #632471

#	Time	Username	Problem	Language	Result	Execution time	Memory
632471		shmad	Mountains (NOI20_mountains)	C++17	2 / 100	20 ms	2676 KiB

Mountains

#pragma GCC optimize("O3", "unroll-loops") // "Ofast" 	
#pragma GCC target("avx2", "bmi", "bmi2", "lzcnt", "popcnt") 

#include <bits/stdc++.h>

//#define int long long
#define vt vector
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
#define ff first
#define ss second
#define dbg(x) cerr << #x << " = " << x << '\n'
#define bit(x, i) ((x) >> (i) & 1)

using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vvt = vt< vt<int> >;

const int N = 1e6 + 5, mod = 1e9 + 7, B = 500;
const ll inf = 1e18 + 7, LIM = (1ll << 60);
const double eps = 1e-6;

int n, h[N];

void solve () {
	cin >> n;
	vt<int> p(n + 1, 0);
	for (int i = 1; i <= n; i++) cin >> h[i], p[i] = p[i - 1] + (h[i] == 0);
	ll ans = 0;
	for (int i = 1; i <= n; i++) {
		if (h[i] == 0) continue;
		if (p[i - 1] != 0 && p[n] - p[i] != 0) ans += min(p[i - 1], p[n] - p[i]);
	}
	cout << ans;
	cout << '\n';
}

bool testcases = 0;

signed main() {
	cin.tie(0) -> sync_with_stdio(0);
	int test = 1;
	if (testcases) cin >> test;
	for (int cs = 1; cs <= test; cs++) {
		solve();
	}
}

• Subtask 1: 2 / 2
• Subtask 2: 0 / 4
• Subtask 3: 0 / 9
• Subtask 4: 0 / 36
• Subtask 5: 0 / 28
• Subtask 6: 0 / 9
• Subtask 7: 0 / 12