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#include<cstdio> #include<algorithm> #define ll long long #define N 200005 using namespace std; int tr[N],b[N],n,x,y; ll ans; struct he{ int d,p; }a[N]; bool cmp(he a,he b){ return a.d<b.d; } int lowbit(int x){ return x&-x; } void add(int x,int u){ for(;x<=n;x+=lowbit(x)) tr[x]+=u; } int get(int x){ int tmp=0; for(;x;x-=lowbit(x)) tmp+=tr[x]; return tmp; } int main(){ while(scanf("%d%d%d",&n,&x,&y)!=EOF){ for(int i=1;i<=n;i++) tr[i]=0; for(int i=1;i<=n;i++) scanf("%d",&a[i].d),a[i].p=i; sort(a+1,a+1+n,cmp); int now=0; a[0].d=a[1].d+1; for(int i=1;i<=n;i++) { if(a[i].d!=a[i-1].d)now++; b[a[i].p]=now; } ans=0; for(int i=n;i>=1;i--){ int x=get(b[i]-1); ans+=x; add(b[i],1); } if(y<x)printf("%lld\n",ans*y);else printf("%lld\n",ans*x); } } |
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