PAT乙级1007（编译未通过）

#include<iostream>using namespace std;int main(){    int m;    cin >> m;    int a[10000] = { 0 };    for (int i = 0; i < m; i++)a[i] = 1;    int i = 2;    while (i<m)    {        for (int j = 2; (j*i) < m; j++)a[j*i] = 0;        i++;        while (a[i] == 0)i++;    }    int tag1=2;    int cnt = 0;    for (int i = 3; i < m; i++)if (a[i]) {        if ((i-tag1)==2)cnt++;        tag1 = i;    }    cout << cnt;}

少了#include
using namespace std;
应该是复制提交的时候的失误