Write a C++ program to print the hollow diamond star pattern using for loop.
#include<iostream> using namespace std; int main() { int i, j, k, rows; cout << "Enter Hollow Diamond Star Pattern Row = "; cin >> rows; cout << "Hollow Diamond Star Pattern\n"; for(i = 1; i <= rows; i++) { for(j = 1; j <= rows - i; j++) { cout << " "; } for(k = 1; k <= i * 2 - 1; k++) { if (k == 1 || k == i * 2 - 1) { cout << "*"; } else { cout << " "; } } cout << "\n"; } for(i = rows - 1; i > 0; i--) { for(j = 1; j <= rows - i; j++) { cout << " "; } for(k = 1; k <= i * 2 - 1; k++) { if (k == 1 || k == i * 2 - 1) { cout << "*"; } else { cout << " "; } } cout << "\n"; } return 0; }

This example prints the hollow diamond pattern of a given character using a while loop.
#include<iostream> using namespace std; int main() { int i = 1, j, k, rows; char ch; cout << "Enter Hollow Diamond Star Pattern Row = "; cin >> rows; cout << "Enter Symbol for Hollow Diamond Pattern = "; cin >> ch; while(i <= rows) { j = 1; while( j <= rows - i) { cout << " "; j++; } k = 1; while( k <= i * 2 - 1) { if (k == 1 || k == i * 2 - 1) { cout << ch; } else { cout << " "; } k++; } cout << "\n"; i++; } i = rows - 1; while( i > 0) { j = 1; while( j <= rows - i) { cout << " "; j++; } k = 1; while( k <= i * 2 - 1) { if (k == 1 || k == i * 2 - 1) { cout << ch; } else { cout << " "; } k++; } cout << "\n"; i--; } return 0; }
Enter Hollow Diamond Star Pattern Row = 15
Enter Symbol for Hollow Diamond Pattern = $
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