Submission #1203438

#	Time	Username	Problem	Language	Result	Execution time	Memory
1203438		trandangquang	Arranging Tickets (JOI17_arranging_tickets)	C++20	85 / 100	6094 ms	12228 KiB

arranging_tickets

#include <bits/stdc++.h>
using namespace std;

#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define sz(a) (int)(a).size()
#define all(a) (a).begin(), (a).end()
#define bit(s, i) (((s) >> (i)) & 1)
#define ii pair <int, int>
#define fi first
#define se second
#define ll long long
#define eb emplace_back
#define pb push_back
#define __builtin_popcount __builtin_popcountll

template <class X, class Y>
    bool maximize(X &x, Y y) {
        if(x < y) {
            x = y;
            return true;
        }
        return false;
    }

template <class X, class Y>
    bool minimize(X &x, Y y) {
        if(x > y) {
            x = y;
            return true;
        }
        return false;
    }

void solve();
int32_t main() {
    #define task "test"
    if(fopen(task".inp", "r")){
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    cin.tie(0)->sync_with_stdio(0);

    int tc = 1; //cin >> tc;
    FOR(i, 1, tc){
        solve();
    }
}

const int N=2e5+5;

int n,m,p; ll a[N],s[N];
vector<ii> seg[N];

bool chk(ll mxB, ll M){
    FOR(i,1,n) s[i]=0;

    priority_queue<ii> pq;
    ll cur=0;
    FOR(i,1,p){
        ll need=(a[i]+mxB-M+1)/2;
        for(auto [x,y]:seg[i]){
            if(x>p){
                pq.push({x,y});
            }
        }
        while(cur<need){
            if(pq.empty()) return false;
            auto [x,y]=pq.top(); pq.pop();
            if(cur+y<=need){
                cur+=y;
                s[x]+=y;
            }
            else{
                s[x]+=need-cur;
                pq.push({x,y-(need-cur)});
                cur=need;
            }
        }
    }
    FOR(i,p+1,n){
        cur-=s[i];
        ll need=(a[i]+mxB-M+1)/2;
        if(cur<need) return false;
    }
    return true;
}

void solve() {
    cin>>n>>m;
    FOR(i,1,m){
        int l,r,c; cin>>l>>r>>c;
        if(l>r) swap(l,r);
        a[l]+=c; a[r]-=c;
        seg[l].eb(r,c);
    }

    p=1;
    FOR(i,1,n){
        a[i]+=a[i-1];
        if(a[i]>a[p]) p=i;
    }

    ll L=1, R=1e14, res=0;
    while(L<=R){
        int M=(L+R)>>1;
        if(chk(a[p]-M,M)||chk(a[p]-M+1,M)){
            res=M;
            R=M-1;
        }
        else{
            L=M+1;
        }
    }
    cout<<res<<'\n';
}

Compilation message (stderr)

arranging_tickets.cpp: In function 'int32_t main()':
arranging_tickets.cpp:39:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   39 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
arranging_tickets.cpp:40:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   40 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 35 / 35
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 0 / 15