Submission #45185532

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Source Code Expand

#include <bits/stdc++.h>
using namespace std;
#define rep(i, f, t) for(int i(f); i <= t; ++i)
#define re(i, t) for(int i(1); i <= t; ++i)
#define per(i, t, f) for(int i(t); i >= f; --i)
#define pe(i, t) for(int i(t); i >= 1; --i)
#define each(i, x) for(auto &i : (x))
#define nx(i, u) for(int i(head[u]); i; i = e[i].nxt) 
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
typedef pair <double, int> pdi;
typedef pair <int, int> pii;
typedef pair <int, pair<int, int> > pipii;
typedef pair <string, bool> psb;
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define mkp make_pair
#define ix(l, r) ((l + r) | (l != r))
#define lowbit(x) (x & -x)
#define inf 0x3f3f3f3f
#define INF 0x3f3f3f3f3f3f3f3f
#define dinf 1000000000000.0
#define eps 1e-10
#define FileIn(x) freopen(x,"r",stdin)
#define FileOut(x) freopen(x,"w",stdout)
#define FileIO(x,y) FileIn(x);FileOut(y)
#define SYSP system("pause")
#define CIOO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0)
#define ls(x) (x << 1)
#define rs(x) (x << 1 | 1)
#define int long long
// #pragma GCC optimize(1)
// #pragma GCC optimize(2)
// #pragma GCC optimize(3,"Ofast")
const int N(3e5+5);
int n,a[N],b[N],cnt[N],tot;
int s1[N],s2[N],pre[N];
signed main(){
    CIOO;
    cin>>n;
    re(i,n){
        cin>>a[i];
    }
    re(i,n){
        cin>>a[i];
    }
    int ans=0;
    re(i,n){
        ans+=s2[a[i]]+(i-s1[a[i]]-1)*s1[a[i]];
        s1[a[i]]++;
        s2[a[i]]+=s1[a[i]]-i;
    }
    cout<<ans;
}

Submission Info

Judge Result