Submission #8095

#	Time	Username	Problem	Language	Result	Execution time	Memory
8095		gs14004	전봇대 (KOI13_pole)	C++98	89 / 100	60 ms	2648 KiB

pole

#include <cstdio>
#include <algorithm>
using namespace std;
typedef long long lint;

struct pole{lint a,i;}d[100005];
int cmp(pole a, pole b){return a.a * b.i < b.a * a.i;}

lint n;
lint trial(lint piv){
    lint res = 0;
    for (int i=0; i<n; i++) {
        res += max(d[i].a - piv * d[i].i, piv * d[i].i - d[i].a);
    }
    return res;
}

int main(){
    scanf("%lld",&n);
    for (int i=0; i<n; i++) {
        scanf("%lld",&d[i].a);
        d[i].i = i;
    }
    sort(d,d+n,cmp);
    int piv;
    lint cum = 0;
    for (piv = 0; piv < n; piv++) {
        cum += d[piv].i;
        if(cum >= n * (n-1) / 4) break;
    }
    lint that = d[piv].a / d[piv].i;
    lint res = 1e16;
    for (lint t = that-2; t <= that+2; t++) {
        if(t > 0)res = min(res,trial(t));
    }
    printf("%lld",res);
}

• Subtask 1: 0 / 11
• Subtask 2: 21 / 21
• Subtask 3: 31 / 31
• Subtask 4: 37 / 37