Submission #1134987

#	Time	Username	Problem	Language	Result	Execution time	Memory
1134987		ByeWorld	Salesman (IOI09_salesman)	C++20	40 / 100	3097 ms	20124 KiB

salesman

#include <bits/stdc++.h>
#define int long long
#define ll long long
#define pb push_back
#define fi first
#define se second
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
#define ld long double
using namespace std;
typedef pair<int,int> pii;
typedef pair<char,char> pcc;
typedef pair<int,pii> ipii;
typedef pair<pii,pii> ipiii;
const int MAXN = 5e5+30;
const int SQRT = 610;
const int MAXA = 5e3+10;
const int MOD = 1e6+7;
const int INF = 1e9+10;
const int LOG = 21;
const ld EPS = 1e-12;
void chmx(int &a, int b){ a = max(a,b); }

int n, u, d, s;
vector <ipii> vec;
int dp[MAXN], dp2[MAXN], a[MAXN];

signed main(){
    // ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n >> u >> d >> s;
    for(int i=1; i<=s-1; i++) dp[i] = -(s-i)*u;
    for(int i=s+1; i<=MAXA; i++) dp[i] = -(i-s)*d;
    dp[0] = -INF; dp[MAXA+1] = -INF;

    for(int i=1; i<=n; i++){
        int d,id,w; cin>>d>>id>>w;
        vec.pb({d, {id,w}});
    }
    sort(vec.begin(), vec.end());

    for(int p=0; p<vec.size(); ){
        int j = p;
        vector <pii> te, te2;
        for(int i=1; i<=MAXA; i++) a[i] = 0, dp2[i] = -INF;
        while(p<vec.size() && vec[p].fi == vec[j].fi){ 
            a[vec[p].se.fi] += vec[p].se.se;
            p++;
        }
        int nw = -INF;
        for(int i=1; i<=MAXA; i++){
            nw -= d; nw = max(nw, dp[i]);
            nw += a[i];
            dp2[i] = nw;
        }
        nw = -INF;
        for(int i=MAXA; i>=1; i--){
            nw -= u; nw = max(nw, dp[i]);
            nw += a[i];
            chmx(dp2[i], nw);
        }
        for(int i=1; i<=MAXA; i++) chmx(dp[i], dp2[i]);
        for(int i=1; i<=MAXA; i++) chmx(dp[i], dp[i-1]-d);
        for(int i=MAXA; i>=1; i--) chmx(dp[i], dp[i+1]-u);
    }
    cout << dp[s] << '\n';
}   

• Subtask 1: 40 / 100