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Codeforces 816B Karen and Coffee(字首和)

To stay woke and attentive during classes, Karen needs some coffee!

Karen, a coffee aficionado, wants to know the optimal temperature for brewing the perfect cup of coffee. Indeed, she has spent some time reading several recipe books, including the universally acclaimed "The Art of the Covfefe".

She knows n coffee recipes. The i-th recipe suggests that coffee should be brewed between li and ri degrees, inclusive, to achieve the optimal taste.

Karen thinks that a temperature is admissible if at least k recipes recommend it.

Karen has a rather fickle mind, and so she asks q

 questions. In each question, given that she only wants to prepare coffee with a temperature between a and b, inclusive, can you tell her how many admissible integer temperatures fall within the range?

Input

The first line of input contains three integers, nk (1 ≤ k

 ≤ n ≤ 200000), and q (1 ≤ q ≤ 200000), the number of recipes, the minimum number of recipes a certain temperature must be recommended by to be admissible, and the number of questions Karen has, respectively.

The next n lines describe the recipes. Specifically, the i-th line among these contains two integers li and ri (1 ≤ li ≤ ri ≤ 200000), describing that the i-th recipe suggests that the coffee be brewed between li and ri degrees, inclusive.

The next q lines describe the questions. Each of these lines contains a and b, (1 ≤ a ≤ b ≤ 200000), describing that she wants to know the number of admissible integer temperatures between a and b degrees, inclusive.

Output

For each question, output a single integer on a line by itself, the number of admissible integer temperatures between a and b degrees, inclusive.

Examples

Input

3 2 4
91 94
92 97
97 99
92 94
93 97
95 96
90 100

Output

3
3
0
4

Input

2 1 1
1 1
200000 200000
90 100

Output

0

Note

In the first test case, Karen knows 3 recipes.

  1. The first one recommends brewing the coffee between 91 and 94 degrees, inclusive.
  2. The second one recommends brewing the coffee between 92 and 97 degrees, inclusive.
  3. The third one recommends brewing the coffee between 97 and 99 degrees, inclusive.

A temperature is admissible if at least 2 recipes recommend it.

She asks 4 questions.

In her first question, she wants to know the number of admissible integer temperatures between 92 and 94 degrees, inclusive. There are 3: 92, 93 and 94degrees are all admissible.

In her second question, she wants to know the number of admissible integer temperatures between 93 and 97 degrees, inclusive. There are 3: 93, 94 and 97degrees are all admissible.

In her third question, she wants to know the number of admissible integer temperatures between 95 and 96 degrees, inclusive. There are none.

In her final question, she wants to know the number of admissible integer temperatures between 90 and 100 degrees, inclusive. There are 4: 92, 93, 94 and 97degrees are all admissible.

In the second test case, Karen knows 2 recipes.

  1. The first one, "wikiHow to make Cold Brew Coffee", recommends brewing the coffee at exactly 1 degree.
  2. The second one, "What good is coffee that isn't brewed at at least 36.3306times the temperature of the surface of the sun?", recommends brewing the coffee at exactly 200000 degrees.

A temperature is admissible if at least 1 recipe recommends it.

In her first and only question, she wants to know the number of admissible integer temperatures that are actually reasonable. There are none.

PS:這是一個球區間覆蓋的題,題目q次詢問就是輸出在詢問區間有多少整數在已經區間出現k次及k次以上的數的個數。

 要想使某個區間同時加上一個數,不需要把每個都加,只需要像lazy tag一樣在起點加上這個數,終點的下一個減去這個數。最後求一遍字首和就一次性的把前面的全部區間都更新了。

#include <iostream>
#include<cstring>
#include<cstdio>
#include<algorithm>
#include<map>
#include<queue>
#include<set>
#include<cmath>
#include<stack>
#include<string>
const int maxn=2e5+10;
const int mod=1e9+7;
const int inf=1e8;
#define me(a,b) memset(a,b,sizeof(a))
#define lowbit(x) x&(-x)
typedef long long ll;
using namespace std;
int main()
{
    int n,k,q;
    int num[maxn],sum[maxn];
    me(num,0),me(sum,0);
    scanf("%d%d%d",&n,&k,&q);
    for(int i=1;i<=n;i++)
    {
        int l,r;
        scanf("%d%d",&l,&r);
        num[l]++,num[r+1]--;//起點加一,終點減一
    }
    for(int i=1;i<maxn;i++)//算字首和,求出在區間範圍內哪些數複合要求,並且記錄下來。
    {
        num[i]+=num[i-1];
        if(num[i]>=k)
            sum[i]++;
    }
    for(int i=1;i<maxn;i++)//求字首和,最後直接兩邊相減,就是所求區間滿足數的個數。
        sum[i]+=sum[i-1];
    while(q--)
    {
        int l,r;
        scanf("%d%d",&l,&r);
        printf("%d\n",sum[r]-sum[l-1]);
    }
    return 0;
}