Submission #526337

#	Time	Username	Problem	Language	Result	Execution time	Memory
526337		keta_tsimakuridze	Mountain Trek Route (IZhO12_route)	C++14	0 / 100	94 ms	9908 KiB

route

#include<bits/stdc++.h>
#define int long long
#define f first
#define s second
#define pii pair<int,int>
using namespace std;
const int N = 2e5 + 5, mod = 1e9 + 7; // !
int t, n, k, p[N], a[N], b[N], l[N], r[N];
int find(int u) {
	return (p[u] == u ? u : p[u] = find(p[u]));
}
void merge(int u, int v) {
	u = find(u); v = find(v);
	if(u == v) return;
	p[v] = u;
	l[u] = min(l[u], l[v]);
	r[u] = max(r[u], r[v]);
}
main(){
	cin >> n >> k;
	pii mx; mx = {0, 0};
	for(int i = 1; i <= n; i++) cin >> b[i], p[i] = i, l[i] = r[i] = i, mx = max(mx, {b[i], i});
	int c = 0;
	for(int i = mx.s; i <= n; i++) a[++c] = b[i];
	for(int i = 1; i < mx.s + 1; i++) a[++c] = b[i];
	set<pii> s;
	for(int i = 1; i <= n; i++) {
		int j = i - 1; 
		while(j < n && a[j + 1] == a[i]) j++, merge(i, j);
		find(i);
		if(a[l[p[i]] - 1] > a[i] && a[r[p[i]] + 1] > a[i]) s.insert({r[p[i]] - l[p[i]] + 1, i}); 
		
		i = j;
	} 
	int ans = 0;
	while(k && s.size()) {
		pii x = *s.begin();
		s.erase(x);
		int i = x.s, len = x.f; find(i);
		i = p[i];
		int need = min(a[l[p[i]] - 1], a[r[p[i]] + 1]) - a[p[i]]; 
		if(need * len >= k) {
			
			ans += k / len * 2; 
			k = 0;
			break;
		}
		ans += need * 2;
		k -= need * len;
		a[p[i]] = min(a[l[p[i]] - 1], a[r[p[i]] + 1]);
		if(a[p[i]] == a[l[p[i]] - 1]) {
			merge(p[i], l[p[i]] - 1);
		}
		if(a[p[i]] == a[r[p[i]] + 1]) {
			merge(p[i], r[p[i]] + 1);
		}
		if(a[l[p[i]] - 1] > a[p[i]] && a[r[p[i]] + 1] > a[p[i]]) s.insert({r[p[i]] - l[p[i]] + 1, i}); 
	}
	cout << ans;
}

Compilation message (stderr)

route.cpp:19:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   19 | main(){
      | ^~~~

• Subtask 1: 0 / 100