5.9.10.cpp

#include<iostream>
using namespace std;

int main()
{
	int rows;
	cout << "Enter number of rows: ";
	cin >> rows;
	for (int i = 1; i <= rows; i++)
	{
		for (int k = 1; k <= rows-i; k++)
			cout << '.';
		for (int j = 1; j <= i; j++)
			cout << '*';
		cout << endl;
	}
	return 0;
}