5. Use for loops to construct a program that displays a pyramid of Xs on the screen.

Chapter 3: 

Loops and Decisions

Programming Exercise

Problem # 5:

Use for loops to construct a program that displays a pyramid of Xs on the screen. The pyramid should look like this
            X
         XXX
      XXXXX
   XXXXXXX
XXXXXXXXX
except that it should be 20 lines high, instead of the 5 lines shown here. One way to do this is to nest two inner loops, one to print spaces and one to print Xs, inside an outer loop that steps down the screen from line to line.

Solution:

#include <iostream>
using namespace std;
#include <conio.h>
int main()
{
    int i, j, k, c=5;
    for(i=1;i<=5;i++)
    {
        for(k=1;k<c;k++)
        {
            cout<<" ";
        }
        for(j=1;j<=(2*i)-1;j++)
        {
            cout<<"X";
        }
        cout<<endl;
        c--;
    }
      
    return 0;
}

Let me know in the comment section if you have any question.

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