#include<algorithm> #include<iostream> #include<cstdio> using namespace std; inline int read(){ int x=0,f=1;char ch=getchar(); while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();} while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();} return x*f; } int n,x,y,a[25001],b[25001]; long long ans; int main(){ n=read();x=read();y=read(); for(int i=1;i<=n;i++) a[i]=read(),b[i]=read(); sort(a+1,a+n+1); sort(b+1,b+n+1); for(int i=1;i<=n;i++) if(b[i]>a[i])ans+=x*(b[i]-a[i]); else ans+=y*(a[i]-b[i]); printf("%lld",ans); return 0; }