D. Powerful array
time limit per test
5 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output
An array of positive integers a1, a2, ..., an is given. Let us consider its arbitrary subarray al, al + 1..., ar, where 1 ≤ l ≤ r ≤ n. For every positive integer s denote by Ks the number of occurrences of s into the subarray. We call the power of the subarray the sum of products Ks·Ks·s for every positive integer s. The sum contains only finite number of nonzero summands as the number of different values in the array is indeed finite.
You should calculate the power of t given subarrays.
Input
First line contains two integers n and t (1 ≤ n, t ≤ 200000) — the array length and the number of queries correspondingly.
Second line contains n positive integers ai (1 ≤ ai ≤ 106) — the elements of the array.
Next t lines contain two positive integers l, r (1 ≤ l ≤ r ≤ n) each — the indices of the left and the right ends of the corresponding subarray.
Output
Output t lines, the i-th line of the output should contain single positive integer — the power of the i-th query subarray.
Please, do not use %lld specificator to read or write 64-bit integers in C++. It is preferred to use cout stream (also you may use %I64d).
Examples
input
Copy
3 2 1 2 1 1 2 1 3
output
Copy
3 6
input
Copy
8 3 1 1 2 2 1 3 1 1 2 7 1 6 2 7
output
Copy
20 20 20
Note
Consider the following array (see the second sample) and its [2, 7] subarray (elements of the subarray are colored):
Then K1 = 3, K2 = 2, K3 = 1, so the power is equal to 32·1 + 22·2 + 12·3 = 20.
(cnt+1)^2*a[i]-cnt^2*a[i] = (2*cnt+1)*a[i];
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define lld I64d
const int MAX = 2e5 + 7;
int A[MAX];
int cnt[MAX * 10];
ll res[MAX];
ll ans = 0;
int n, sz;
struct node{
int l, r, id;
bool operator < (const node &a) const{
if(l / sz == a.l / sz)
return r < a.r;
return l / sz < a.l / sz;
}
} a[MAX];
void add(int pos){
ll x = cnt[A[pos]];
ans += (2ll * x + 1ll) * A[pos];
cnt[A[pos]]++;
}
void del(int pos){
ll x = cnt[A[pos]];
ans += (-2ll * x + 1ll) * A[pos];
cnt[A[pos]]--;
}
int main(){
int m;
scanf("%d%d", &n, &m);
sz = sqrt(n);
for(int i = 0; i < n; i++)
scanf("%d", &A[i]);
for(int i = 0; i < m; i++){
scanf("%d%d", &a[i].l, &a[i].r);
a[i].l--;
a[i].r--;
a[i].id = i;
}
sort(a, a + m);
int p = 0, q = 0;
for(int i = 0; i < m; i++){
int L = a[i].l;
int R = a[i].r;
while(p < L){
del(p);
p++;
}
while(p > L){
add(p - 1);
p--;
}
while(q <= R){
add(q);
q++;
}
while(q > R + 1){
del(q - 1);
q--;
}
res[a[i].id] = ans;
}
for(int i = 0; i < m; i++)
printf("%lld\n", res[i]);
return 0;
}