C++ For Loop_1.8

#include <iostream>
using namespace std;
int main (void)
{
    int i,j;
    freopen("out.txt","w",stdout);
    for(i=1;i<=5;i++)
    {
       for(j=1;j<=i+i-1;j++)
       cout<< j;
       cout<< "\n";
    }
}

The Output is Given Below:

1
123
12345
1234567
123456789