Hello. Im trying to make a pyramid of strings with my name in it

#include<iostream>
#include<string>
using namespace std;
int main(){
    [the image shows the error I keep getting]
    string st("HabibRehman");
    string a="", b="";
    int y=st.length();
    int d=y/2;
    int f;
    f=d;
    for(int i=1;i<st.length();i++){
        for( int j=0;j<y;j++){
            cout<<" ";
        }
        for(int k=0;k<1;k++)/*I'm not sure what this loop should be*/{
            cout<<a+st.substr(d,i)<<endl;
            /*int d=(st.length()/2);
            static int f=d;//I was trying to keep the values static here
            static int g=d;*/
            //this doesn't work in here

        }
        --f;//if i put this outside the for loop it works wrong without the termination error.
        a=st.substr(f,i);//I'm using this to get the value prior to the st.substr(d,i)
        y--;
    }
    system("pause");
    retu 0;
}

I keep getting a termination error. Ive tried almost everything I knew like changing the loops, the positions of substrings and variables, when I get the output I want, the program gives me an termination error, otherwise it gives me a wrong output without the termination error.