#include <stdio.h>

int main() {
    const int HEIGHT = 15;
    const int OFFSET = 20;
    const int FREQ   = 5;

    for (int count = 0, i = 0; i < HEIGHT; ++i) {
        for (int j = 0; j < OFFSET - i; ++j)
            putchar(' ');

        for (int j = 0; j < 2 * i + 1; ++j)
            putchar(count++ % FREQ ? '*' : 'o');

        puts("");
        }
    }