#include "stdafx.h"
#include <iostream>
#include <sstream>
#include <string>
using namespace std;
int main() {
// initialize variables
string str;
int num;
int count = 1;
bool sur = true;
// user input
cout << "Enter how many stars: "; getline(cin, str); stringstream(str) >> num;
// test for null
if (str.length() < 1) { num = 0; };
// make sure number is positive
num = abs(num);
cout << '\n';
if (num) {
while (count != 0) {
for (int i = 1; i <= count; i++) {
cout << char(42);
}
cout << "\n";
if (count == num) {
sur = false;
}
if (sur == true) { count++; }
else { count--; }
}
}
else { cout << "Invalid number!"; }
// wait
// getchar();
system("pause"); // for visual studio
return 0;
}
Output
Notes
#include "stdafx.h"
#include <iostream>
using namespace std;
int main() {
// input
cout << "Enter depth of pyramid: \n";
int n;
cin >> n;
cout << "\n";
// ascending
for (int i = 1; i <= n; i++) {
for (int j = 0; j <i; j++)
cout << "*";
cout << endl;
}
// descending
for (int i = n - 1; i >0; i--) {
for (int j = i; j > 0; j--)
cout << "*";
cout << endl;
}
// wait
system("pause");
return 0;
}