Cod sursa(job #1855692)

Utilizator TimitocArdelean Andrei Timotei Timitoc Data 23 ianuarie 2017 20:56:41
Problema Stalpi Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.14 kb
#include <iostream>
#include <cstdio>
#include <algorithm>
#define MAXN 100050
#define inf 0x3f3f3f3f

using namespace std;

struct stalp
{
    int st, dr, c;
    bool operator<(const stalp &e) const
    {
        return dr < e.dr;
    }
}s[MAXN];
int x[MAXN], aib[MAXN], n;

int query(int pos)
{
    if (!pos) return 0;
    int mini = inf;
    for (pos; pos <= n; pos += pos & -pos)
        mini = min(mini, aib[pos]);
    return mini;
}

void update(int pos, int val)
{
    for (pos; pos; pos -= pos & -pos)
        aib[pos] = min(aib[pos], val);
}

int main()
{
    freopen("stalpi.in", "r", stdin);
    freopen("stalpi.out", "w", stdout);

    scanf("%d", &n);
    for (int i = 1; i <= n; i++) {
        scanf("%d %d %d %d", &x[i], &s[i].c, &s[i].st, &s[i].dr);
        s[i].st = x[i]-s[i].st;
        s[i].dr += x[i];
        aib[i] = inf;
    }
    sort(x+1, x+n+1);
    sort(s+1, s+n+1);
    for (int i = 1; i <= n; i++)
    {
        int best = query(lower_bound(x+1, x+n+1, s[i].st)-x-1);
        update(upper_bound(x+1, x+n+1, s[i].dr)-x-1, best + s[i].c);
    }
    printf("%d", aib[n]);

    return 0;
}