C++ Program for triangular pattern (mirror image around 0)

Given with the positive value n and the task is to generate the triangular pattern i.e. mirror image of the printed numbers and display the result

Example

Input-: n = 6
Output-:

Input-: n = 3
Output-:

Approach used in the below program is as follows −

• Input the value of n as a positive integer
• Traverse one loop i for the number of rows in a pattern i.e. n
• Traverse one loop j for the number of spaces in a pattern
• Traverse another loop for the digits in a pattern

Algorithm

START
Step 1-> declare function to print mirror image of triangular pattern
   void print_mirror(int n)
   declare and set int temp = 1 and temp2 = 1
      Loop for int i = 0 and i < n and i++
         Loop For int j = n - 1 and j > i and j—
            print space
         End
         Loop For int k = 1 and k <= temp and k++
            print abs(k - temp2)
         End
         Set temp += 2
         increment temp2++
         print \n
Step 2-> In main()
   Declare int n = 6
   print_mirror(n)
STOP

Example

#include <bits/stdc++.h>
using namespace std;
//function to print mirror image of triangular pattern
void print_mirror(int n) {
   int temp = 1, temp2 = 1;
   for (int i = 0; i < n; i++) {
      for (int j = n - 1; j > i; j--) {
         cout << " ";
      }
      for (int k = 1; k <= temp; k++) {
         cout << abs(k - temp2);
      }
      temp += 2;
      temp2++;
      cout << "\n";
    }
}
int main() {
   int n = 6;
   print_mirror(n);
   return 0;
}

Output