Gym 100187M - Heaviside Function

Heaviside function is defined as the piecewiseconstant function whose value is zero for negative argument and one fornon-negative argument:

You are given the function f(x) = θ(s_1x - a₁) + θ(s_2x - a₂) + ... + θ(s_nx - a_n), where s_i =  ± 1. Calculate its values for argument values x₁, x₂, ..., x_m.

Input

The first line contains a single integer n (1 ≤ n ≤ 200000) —the number of the summands in the function.

Each of the next n lines contains two integers separated byspace — s_i and a_i (s_i =  ± 1,  - 10⁹ ≤ a_i ≤ 10⁹) — parameters of thei-th summand.

The next line contains a single integer m (1 ≤ m ≤ 200000) —the number of the argument values you should calculate the value of thefunction for.

The last line contains m integers x₁, ..., x_m ( - 10⁹ ≤ x_i ≤ 10⁹) separated by spaces — the argument valuesthemselves.

Output

Output m lines. i-th line should contain the value of f(x_i).

Sample test(s)

input

6
1 3
-1 2
1 9
-1 2
1 7
-1 2
8
0 12 2 8 4 -3 7 9

output

0
3
0
2
1
3
2
3

 

思路：

将s=1与s=-1的分开分别用a1,a2两个数组存储，分别从小到大排序；

x用结构存储，记录值和输入顺序，并按数值从小到大排序；

对于s=1，即对于a1数组，则统计x-a1[i]>=0的个数，我们可以枚举x，a1[i]从最大的开始，当a[i]足够小时，统计a1[i]的剩余个数。因为我们事先已经排序，所以直接加就可以；

对于s=-1的情况，同理；

代码：#define _CRT_SECURE_NO_WARNINGS#include <iostream>#include <cstdio>#include <cstring>#include <queue>#include <algorithm>using namespace std;const int N = 200005;int n, s;int a1[N], a2[N];int l1, l2;int m;struct node{int value, id;}x[N];__int64 ans[N];bool cmp(node a, node b){return a.value<b.value;}bool cmp2(node a, node b){return a.id<b.id;}int main(){memset(ans, 0, sizeof(ans));scanf("%d", &n);int i, temp;l1 = l2 = 0;for (i = 0; i<n; i++){scanf("%d%d", &s, &temp);if (s == 1)a1[l1++] = temp;elsea2[l2++] = temp;}scanf("%d", &m);for (i = 0; i<m; i++){scanf("%d", &x[i].value);x[i].id = i;}sort(a1, a1 + l1);sort(a2, a2 + l2);sort(x, x + m, cmp);for (i = m - 1; i >= 0; i--){if (l1 == 0)break;while (x[i].value<a1[l1 - 1] && l1>0)l1--;if (l1 == 0)break;ans[x[i].id] += l1;}for (i = 0; i<m; i++){if (l2 == 0)break;while (x[i].value>-a2[l2 - 1] && l2>0)l2--;if (l2 == 0)break;ans[x[i].id] += l2;}sort(x, x + m, cmp2);for (i = 0; i<m; i++)printf("%I64d\n", ans[i]);return 0;}