CTNEWS - Lâu đài cát
Tác giả: RR
Ngôn ngữ: C++
#include <cstdio>
#include <iostream>
#include <algorithm>
#define MAXN 25111
#define FOR(i,a,b) for(long i=a; i<=b; i++)
using namespace std;
long a[MAXN],b[MAXN],x,y,n;
int main() {
scanf("%ld %ld %ld",&n,&x,&y);
FOR(i,0,n-1) scanf("%ld %ld",&a[i],&b[i]);
sort(a,a+n);
sort(b,b+n);
long long res=0;
FOR(i,0,n-1)
if (a[i]<b[i]) res+=(long long) (b[i]-a[i])*x;
else res+=(long long) (a[i]-b[i])*y;
cout<<res;
return 0;
}