Pattern Printing – Half Pyramid Using Asterisk

Print a half pyramid pattern using asterisks (*) with N rows, where each row contains increasing number of asterisks separated by spaces.

Understand the Problem

Problem Statement

The number of rows N is passed as the input. The program must print the half pyramid using asterisk *.

Constraints

2 ≤ N ≤ 100
Each row should contain asterisks separated by single spaces
No trailing spaces at the end of lines

Examples

Example 1

Input

Output

*
* *
* * *
* * * *
* * * * *

Explanation

For N=5, we print 5 rows. Row 1 has 1 asterisk, row 2 has 2 asterisks, and so on until row 5 which has 5 asterisks. Each asterisk is separated by a single space.

Example 2

Input

Output

*
* *
* * *

Explanation

For N=3, we print 3 rows. Row 1 has 1 asterisk, row 2 has 2 asterisks, and row 3 has 3 asterisks, each separated by single spaces.

Solution

#include <stdio.h>

int main() {
    int n;
    scanf("%d", &n);
    
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= i; j++) {
            printf("*");
            if (j < i) {
                printf(" ");
            }
        }
        printf("\n");
    }
    
    return 0;
}

Time:O(N²)

Space:O(1)

Approach:

Step-by-step explanation:

Read the input N using scanf
Outer loop (i): iterates from 1 to N, representing each row
Inner loop (j): for each row i, prints i asterisks
After each asterisk (except the last one in a row), print a space
After completing each row, print a newline character
Time complexity: O(N²) - nested loops
Space complexity: O(1) - only using a few integer variables

Visual Explanation

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