C++ program to print an lower triangle using stars.

#include<iostream.h>
#include<conio.h>
void main()
{
  int j,i,k,l;
  char c;
  clrscr();
  do
  {
     cout<<"Enter the number of stars in the base..";
     cin>>k;
     for (i=1;i<=k;i++)
     {    
         for (j=1;j<=i;j++)
            cout<<"* ";
         cout<<endl;
     }
     cout<<"\nWant to try more..(y/n)\n";
     cin>>c;
  }
  while(c=='y');
  getch();
}

Program to check if the given Value is of type Int in CPP

 

#include <iostream>
using namespace std;

bool isNumber(string s)
{
    for (int i = 0; i < s.length(); i++)
        if (isdigit(s[i]) == false)
            return false;
 
    return true;
}

int main() {
    // Saving the input in a string
    string str = "";
    
    cout << "Enter Value.\n";
    cin >> str;
 
    // Function returns 1 if all elements
    // are in range '0-9'
    if (isNumber(str))
        cout << "Entered Value is Integer";
 
    // Function returns 0 if the input is
    // not an integer
    else
        cout << "Entered Value is String";
        
    return 0;
}