/* 

  Program: Pattern Printing — Right-angled and Centered Pyramids (U2)

  What it does:

    - Reads row count r.

    - Prints: (1) Right-angled triangle of '*' of height r.

              (2) Centered pyramid of '*' of height r.

*/

#include <stdio.h>

int main(void) {

    int r;

    printf("Enter rows (>=1): ");

    if (scanf("%d", &r) != 1 || r < 1) {

        printf("Invalid row count.

");

        return 0;

    }

    /* Right-angled pyramid */

    for (int i = 1; i <= r; ++i) {

        for (int j = 1; j <= i; ++j) printf("*");

        printf("

");

    }

    printf("

");

    /* Centered pyramid */

    for (int i = 1; i <= r; ++i) {

        for (int sp = 1; sp <= r - i; ++sp) printf(" ");

        for (int st = 1; st <= (2 * i - 1); ++st) printf("*");

        printf("

");

    }

    return 0;

}