Printing triangle without nested conditionals - c++

Question

#include<iostream>
using namespace std;
int main() {
int height, star{ 0 };
cout << "Enter height of triangle";
cin >> height;
for(int i=1; i<=height; i++)
{
if(star<i)
{
cout << "*";
++star;
continue;
}
cout << endl;
star = 0;
}
}
This is printing stars in a line
I want to print one star in 1st line then 2 in second line and so forth.
Example:
*
**
***
****
Image:

Answer 1

You should be able to simply do this:
#include <iostream>
using namespace std;
int main()
{
int height;
cout << "Enter height of triangle";
cin >> height;
for(int i=1; i<=height; i++)
{
cout << string(i, '*') << endl;
}
}

Answer 2

You could do this. This uses the length of the string directly instead of a separate counter i.
#include <iostream>
#include <string>
int main() {
int height;
std::cout << "Enter height of triangle";
std::cin >> height;
for(std::string stars = "*"; stars.length() <= height; stars += "*")
{
std::cout << stars << std::endl;
}
return 0;
}

Answer 3

I don't really understand the reason for your question, but hey, why not:
#include <iostream>
#include <string>
int main() {
int height;
std::cout << "Enter height of triangle";
std::cin >> height;
std::string stars = "*";
for(int i=1; i<=height; i++)
{
std::cout << stars << std::endl;
stars += "*";
}
return 0;
}

Answer 4

No loops:
void stars(int height) {
if (!height) return;
stars(height-1);
std::cout << std::string(height, '*') << '\n';
}
int main() {
int height;
std::cout << "Enter height of triangle";
std::cin >> height;
stars(height);
}
Or to not use the loop in std::string(height, '*') as idz suggested:
void stars(int height, std::string &s) {
if (!height) return;
std::cout << s << '\n';
stars(height-1, s+='*');
}
int main() {
int height;
std::cout << "Enter height of triangle\n";
std::cin >> height;
std::string s = "*";
stars(height, s);
}

Answer 5

Here is a C inspired solution. Don't write C++ like this. It's essentially just to show another way to do it than the already posted solutions:
#include <iostream>
int main() {
int height;
std::cout << "Enter height of triangle";
std::cin >> height;
char *arr = new char[height];
std::fill(arr, arr+height+1, '\0');
for(int i=0; i<height; i++) {
arr[i] = '*';
std::cout << arr << std::endl;
}
delete arr;
}

Answer 6

Not necessarily a good solution, but it's an option:
#include <iomanip>
#include <iostream>
int main() {
int height;
std::cout << "Enter height of triangle";
std::cin >> height;
std::cout << std::setfill('*'); // fill the default blank spaces with * instead
++height;
for(int i = 2; i <= height; ++i) {
std::cout << std::setw(i) << '\n'; // fill width i until the newline
}
}

Answer 7

first of all it's not a half triangle it's a triangle or for you we can count that a half rectangle
but leaving that one here what you are looking for is most likely this way
#include <bits/stdc++.h>
for making it easier
using namespace std ;
/*you can always use std::"command" when you ain't using absolute standard name spaces but leaving that one there*/
int main ()
{
for ( string s = "Symbol" ; s.length() <= h ;s += "Symbol" )
{
cout << s << "\n" ;
}
return 0 ;
}