Educational Codeforces Round 2 B. Queries about less or equal elements (二分)

B. Queries about less or equal elements
time limit per test
2 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

You are given two arrays of integers a and b. For each element of the second array bj you should find the number of elements in arraya that are less than or equal to the value bj.

Input

The first line contains two integers n, m (1 ≤ n, m ≤ 2·105) — the sizes of arrays a and b.

The second line contains n integers — the elements of array a ( - 109 ≤ ai ≤ 109).

The third line contains m integers — the elements of array b ( - 109 ≤ bj ≤ 109).

Output

Print m integers, separated by spaces: the j-th of which is equal to the number of such elements in array a that are less than or equal to the value bj.

Sample test(s)
input
5 4
1 3 5 7 9
6 4 2 8
output
3 2 1 4
input
5 5
1 2 1 2 5
3 1 4 1 5
output
4 2 4 2 5




题意:给你一个序列A,然后一个序列B,求在序列A中小于Bi的数的个数


思路:将A序列排序,然后二分查找


总结:刚开始二分写挫了,WA了一发。。。


ac代码:

#include<stdio.h>
#include<math.h>
#include<string.h>
#include<stack>
#include<queue>
#include<vector>
#include<iostream>
#include<algorithm>
#define MAXN 1000010
#define LL long long
#define ll __int64
#define INF 0xfffffff
#define mem(x) memset(x,0,sizeof(x))
#define PI acos(-1)
using namespace std;
ll a[MAXN];
int main()
{
	int n,m;
	int i;
	ll b;
	while(scanf("%d%d",&n,&m)!=EOF)
	{
		for(i=1;i<=n;i++)
		scanf("%I64d",&a[i]);
		sort(a+1,a+n+1);
		while(m--)
		{
			scanf("%I64d",&b);
			int high=n,low=1;
			int k=0;
			int bz=0;
			while(low<=high)
			{
				int mid=(low+high)/2;
				if(a[mid]<=b)
				low=mid+1;
				//else if(a[mid]>b)
				else
				high=mid-1;
			}
			printf(m?"%d ":"%d\n",low-1);
		}
	}
	return 0;
}


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