# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1165369 | Zero_OP | Meetings (IOI18_meetings) | C++20 | 0 ms | 0 KiB |
#include <bits/stdc++.h>
#idndef LOCAL
#include "meetings.h"
#endif //nLOCAL
using namespace std;
#define FOR(i, l, r) for(int i = (l); i < (r); ++i)
#define ROF(i, r, l) for(int i = (r) - 1; i >= (l); --i)
#define mp make_pair
#define mt make_tuple
#define ff first
#define ss second
#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)
#define pb push_back
#define eb emplace_back
#define sz(v) (int)v.size()
#define sum_of(v) accumulate(all(v), 0ll)
#define compact(v) v.erase(unique(all(v)), end(v))
#define dbg(x) "[" #x " = " << (x) << "]"
template<typename T>
bool minimize(T& a, const T& b){
if(a > b) return a = b, true;
return false;
}
template<typename T>
bool maximize(T& a, const T& b){
if(a < b) return a = b, true;
return false;
}
using ll = long long;
using db = double;
using ld = long double;
using ull = unsigned long long;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<db, db>;
using vi = vector<int>;
using vb = vector<bool>;
using vc = vector<char>;
using vl = vector<ll>;
using vd = vector<db>;
using vpi = vector<pi>;
using vpl = vector<pl>;
vl minimum_costs(vi H, vi L, vi R){
int N = sz(H);
int Q = sz(L);
vl result(Q), f(N);
FOR(_, 0, Q){
stack<pi> st;
ll sum = 0;
FOR(i, L[_], R[_]+1){
int cnt = 1;
while(!st.empty() && st.top().ff <= H[i]){
sum -= 1LL * st.top().ff * st.top().ss;
cnt += st.top().ss;
st.pop();
}
sum += 1LL * H[i] * cnt;
st.push(mp(H[i], cnt));
f[i] = sum;
// cout << dbg(i) << dbg(sum) << '\n';
}
sum = 0;
stack<pi>().swap(st);
ll ans = 1e18;
ROF(i, R[_]+1, L[_]){
int cnt = 1;
while(!st.empty() && st.top().ff <= H[i]){
sum -= 1LL * st.top().ff * st.top().ss;
cnt += st.top().ss;
st.pop();
}
sum += 1LL * H[i] * cnt;
st.push(mp(H[i], cnt));
f[i] += sum;
minimize(ans, f[i] - H[i]);
// cout << dbg(i) << dbg(sum) << '\n';
}
result[_] = ans;
}
return result;
}
#ifdef LOCAL
void setIO(){
ios_base::sync_with_stdio(0); cin.tie(0);
#ifdef LOCAL
freopen("task.inp", "r", stdin);
freopen("task.out", "w", stdout);
#endif // LOCAL
}
int main(){
setIO();
int N, Q;
cin >> N >> Q;
vi H(N);
FOR(i, 0, N) cin >> H[i];
vi L(Q), R(Q);
FOR(i, 0, Q) cin >> L[i] >> R[i];
vl costs = minimum_costs(H, L, R);
FOR(i, 0, Q) cout << costs[i] << '\n';
return 0;
}
#endif //LOCAL