CodeForces 86D Powerful array（莫队+优化）

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 productsKs·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

output

3

6

input

8 3

1 1 2 2 1 3 1 1

2 7

1 6

2 7

output

Note

Consider the following array (see the second sample) and its [2, 7] subarray (elements of the subarray are colored):

CodeForces 86D Powerful array（莫队+优化） Then K1 = 3, K2 = 2, K3 = 1, so the power is equal to 32·1 + 22·2 + 12·3 = 20.

题目链接：CF 86D

用自定义函数来排序会超时的一道题超时N次看了大牛的博客发现把块写到结构体里面速度比较快；把add和del函数写到while里面也可以加快速度，再加上位运算会快一点（注意一下优先级）

代码：

#include<iostream>

#include<algorithm>

#include<cstdlib>

#include<sstream>

#include<cstring>

#include<bitset>

#include<cstdio>

#include<string>

#include<deque>

#include<stack>

#include<cmath>

#include<queue>

#include<set>

#include<map>

using namespace std;

#define INF 0x3f3f3f3f

#define CLR(x,y) memset(x,y,sizeof(x))

#define LC(x) (x<<1)

#define RC(x) ((x<<1)+1)

#define MID(x,y) ((x+y)>>1)

typedef pair<int,int> pii;

typedef long long LL;

const double PI=acos(-1.0);

const int N=200010;

const int M=1000010;

LL cnt[M];

int arr[N];

LL ans[N];

int unit;

struct info

{

	int l,r;

	int d;

	int b;

	bool operator<(const info &t)const

	{

		if(b==t.b)

			return r<t.r;

		return b<t.b;

	}

};

info node[N];

int main(void)

{

	int n,m,i,j;

	scanf("%d%d",&n,&m);

	unit=(int)sqrt(n+0.5);

	for (i=1; i<=n; ++i)

		scanf("%d",&arr[i]);

	for (i=0; i<m; ++i)

	{

		scanf("%d%d",&node[i].l,&node[i].r);

		node[i].d=i;

		node[i].b=node[i].l/unit;

	}

	sort(node,node+m);

	int L=node[0].l;

	int R=L-1;

	LL power=0;

	for (i=0; i<m; ++i)

	{

		while (L>node[i].l)

		{

			--L;

			power=power+arr[L]*((cnt[arr[L]]<<1)+1);

			++cnt[arr[L]];

		}

		while (L<node[i].l)

		{

			--cnt[arr[L]];

			power=power-arr[L]*((cnt[arr[L]]<<1)+1);

			++L;

		}

		while (R>node[i].r)

		{

			--cnt[arr[R]];

			power=power-arr[R]*((cnt[arr[R]]<<1)+1);

			--R;

		}

		while (R<node[i].r)

		{

			++R;

			power=power+arr[R]*((cnt[arr[R]]<<1)+1);

			++cnt[arr[R]];

		}

		ans[node[i].d]=power;

	}

	for (i=0; i<m; ++i)

		printf("%I64d\n",ans[i]);

	return 0;

}

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CodeForces 86D Powerful array（莫队+优化）

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