Submission #13867

#	Time	Username	Problem	Language	Result	Execution time	Memory
13867		gs14004	사회적 불평등 (TOKI14_social)	C++14	100 / 100	69 ms	2176 KiB

social

#include <cstdio>
#include <cstring>
#include <utility>
#include <algorithm>
using namespace std;
typedef pair<int,int> pi;
const int MAX = 10000;
typedef long long lint;
 
int n;
pi a[100005];
 
struct bit{
    lint tree[10005];
    int lim;
    void init(int n){
        memset(tree,0,sizeof(tree));
        lim = n + 1;
    }
    void add(int x, int v){
        x++;
        while(x <= lim){
            tree[x] += v;
            x += x & -x;
        }
    }
    lint S(int x){
        x++;
        lint ret = 0;
        while(x){
            ret += tree[x];
            x -= x & -x;
        }
        return ret;
    }
    lint sum(int x, int y){
        return S(y) - S(x-1);
    }
}bit1, bit2, bit3, bit4;
 
lint solve(){
    lint ret = 0;
    bit1.init(MAX);
    bit2.init(MAX);
    bit3.init(MAX);
    bit4.init(MAX);
    for (int i=n-1; i>=0; i--) {
        ret += 1ll * bit1.sum(a[i].second+1,MAX) * a[i].first * a[i].second;
        ret += 1ll * bit2.sum(a[i].second+1,MAX);
        ret -= 1ll * a[i].first * bit3.sum(a[i].second+1,MAX);
        ret -= 1ll * a[i].second * bit4.sum(a[i].second+1,MAX);
        bit1.add(a[i].second,1);
        bit2.add(a[i].second,a[i].first * a[i].second);
        bit3.add(a[i].second,a[i].second);
        bit4.add(a[i].second,a[i].first);
    }
    return ret;
}
 
 
int main(){
    scanf("%d",&n);
    for (int i=0; i<n; i++) {
        scanf("%d %d",&a[i].first,&a[i].second);
    }
    sort(a,a+n);
    lint ret = solve();
    for (int i=0; i<n; i++) {
        a[i].second = MAX + 1 - a[i].second;
    }
    ret += solve();
    printf("%lld",ret);
}

• Subtask 1: 29 / 29
• Subtask 2: 19 / 19
• Subtask 3: 20 / 20
• Subtask 4: 32 / 32