View Compilation Error

0_0_13813843_19549.cpp:1:429: fatal error: GCC4.9.2/lib/gcc/x86_64-w64-mingw32/4.9.2/include/iostream>usin: Invalid argument
 #include<iostream>using namespace std;int prime(int x){   int i;    for(i=x/2+1;i>1;i--)      if(x%i==0)return   0;    return 1;}int main(){   int n,i,j,c;    while(cin>>n&&n)    { c=0;       for(i=2;i<n/2;i++)      { if(prime(i))        for(j=n;j>n/2;j--)          if(prime(j)&&i+j==n)c++;      }      cout<<c<<endl;    }    system("pause");    return 0;}结果超时，求高手给高效方法，只要有思想即可。                            
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compilation terminated.