Not Displaying Spaces

Question

I'm very new to c++ and everything in general. I dont understand why my code doesn't work:

#include <cstdio>

int main(){
 
int a;

scanf("%d", &a);

for(int i = 1; i < a; i++){
 printf(" ");

}

printf("*");

}

what I'm trying to do is make the number of spaces as the value inputted by the user minus and add a * at the end so if a = 10 :

     *

but when I try it the spaces don't show. Ideally what I'm trying to do is get an output something like:

   *
  **
 ***
****

The length depends on user input if it was 10 then the spaces would be 9 and the * at the end would be the tenth.

Answer 1

You will have to use 3 for-loops (two of them nested inside one). The parent for loop for each row. And the nested two are for spaces and stars.

#include <cstdio>
int main()
{

    int a;

    scanf("%d", &a);

    for(int i=1; i<a; i++)
    {
        for(int j=i; j<a; j++)
            printf(" ");
        for(int k=0; k<i; k++)
            printf("*");

        printf("\n");
    }
    return 0;
}

You will get your desired output if you put the value 5 for a, i.e., a=5.

To learn more in detail, you can follow this link star patterns in c

Your code may contain many errors. That's understandable, cause you are new to C/C++. Try problem-solving in beecrowd to improve your problem-solving capabilities and learn C/C++ in a better way. These errors will automatically go away day by day as you progress. But the secret is to practice and never give up. Good luck!