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#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
long long ans=0;
int a[100001],c[100001];
void merge(int l,int r){
    if(l>=r) return;
    merge(l,(l+r>>1));
    merge((l+r>>1)+1,r);
    int p1=l,mid=l+r>>1,p2=mid+1,p3=l;
    while(p1<=mid&&p2<=r){
        if(a[p1]>a[p2]){
            ans+=mid-p1+1;
            c[p3++]=a[p2++];
        }else c[p3++]=a[p1++];
    }
    while(p1<=mid) c[p3++]=a[p1++];
    while(p2<=r) c[p3++]=a[p2++];
    memcpy(a+l,c+l,(sizeof(int))*(r-l+1));
}
char str[8000000],*p=str;
inline int read(){
    int x=0;
    while(!isdigit(*p)) p++;
    while(isdigit(*p)) x=x*10+*p++-48;
    return x;
}
int main(){
    fread(str,1,8000000,stdin);
    int n=read();
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