Problem:
Search II

You are given a sequence of n integers S and a sequence of different q integers T. Write a program which outputs C, the number of integers in T which are also in the set S.

Input

In the first line n is given. In the second line, n integers are given. In the third line q is given. Then, in the fourth line, q integers are given.

Output

Print C in a line.

Constraints

Elements in S is sorted in ascending order

n ≤ 100000

q ≤ 50000

0 ≤ an element in S ≤ 109

0 ≤ an element in T ≤ 109

Sample Input 1

5
1 2 3 4 5
3
3 4 1

Sample Output 1

3

Sample Input 2

3
1 2 3
1
5

Sample Output 2

0

Sample Input 3

5
1 1 2 2 3
2
1 2

Sample Output 3

2

Notes

Solution in C (judge verdict: Accepted)

//二分探索

#include<stdio.h>
#include<stdlib.h>

int main(void){
  int n,q,work;
  int *S;
  int i;
  int left=0,right,cnt=0;

  scanf("%d",&n);

  right=n;

  S=(int *)malloc(sizeof(int)*n);

  for(i=0;i<n;i++)scanf("%d",&S[i]);

  scanf("%d",&q);

  for(i=0;i<q;i++){
    scanf("%d",&work);
    while(1){
      if(left==right) break;

      if(S[(left+right)/2]==work){
	cnt++;
	break;
      }

      if(S[(left+right)/2]>work) right=(left+right)/2;

      if(S[(left+right)/2]<work) left=(left+right)/2+1;
    }
    left=0;
    right=n;
  }

  printf("%d\n",cnt);

  free(S);

  return 0;
}