Submission #946949

#	Time	Username	Problem	Language	Result	Execution time	Memory
946949		phoenix0423	Constellation 3 (JOI20_constellation3)	C++17	100 / 100	158 ms	32976 KiB

constellation3

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> pll;
#define fastio ios::sync_with_stdio(false), cin.tie(0)
#define pb push_back
#define eb emplace_back
#define f first
#define s second
#define int long long 
#define lowbit(x) x&-x
const int maxn = 2e5 + 5;
int BIT[maxn];
int l[maxn], r[maxn], h[maxn];
vector<int> mg[maxn];
vector<pll> star[maxn];
int n;

void upd(int pos, int val){
    while(pos < maxn){
        BIT[pos] += val;
        pos += lowbit(pos);
    }
}

int qry(int pos){
    if(pos < 0) return 0;
    int ret = 0;
    while(pos){
        ret += BIT[pos];
        pos -= lowbit(pos);
    }
    return ret;
}
int rootl(int x){ return l[x] == x ? l[x] : l[x] = rootl(l[x]);}
int rootr(int x){ return r[x] == x ? r[x] : r[x] = rootr(r[x]);}
void merge(int a, int b){
    l[b] = rootl(a);
    r[a] = rootr(b);
}

signed main(void){
    fastio;
    cin>>n;
    for(int i = 1; i <= n; i++) l[i] = r[i] = i;
    for(int i = 1; i <= n; i++){
        cin>>h[i];
        mg[h[i]].pb(i);
    }
    int m;
    cin>>m;
    for(int i = 0; i < m; i++){
        int a, b, w;
        cin>>a>>b>>w;
        star[b].eb(a, w);
    }
    int ans = 0;
    for(int i = 1; i <= n; i++){
        for(auto [x, w] : star[i]){
            l[x] = rootl(l[x]), r[x] = rootr(r[x]);
            int val = qry(x);
            if(val > w) ans += w;
            else ans += val, upd(l[x], w - val), upd(r[x] + 1, val - w);
        }
        for(auto x : mg[i]){
            if(x > 1 && h[x - 1] <= h[x]) merge(x - 1, x);
            if(x < n && h[x + 1] <= h[x]) merge(x, x + 1);
        }
    }
    cout<<ans<<"\n";
}

• Subtask 1: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 65 / 65