C++ Program for While Loop

Program 1

// Program for while loop 1+ 2+3+4+5
#include<iostream>
using namespace std;
#define clrscr() system("cls")
int main()
{
    int i,n,sum=0;
    clrscr();  
    i=1;  // intilization
    cout<<"Enter the limit";
    cin>>n;
    while(i<=n)  //condition
    {
        cout<<i<<"\n";
        sum+=i;  // sum=sum+i
        i++;
    }
    cout<<"__________________";
    cout<<"\n Sum is :"<<sum;
    return 0;
}

Program 2

// Program for table of number
#include<iostream>
using namespace std;
#define clrscr() system("cls")
int main()
{
    int n,i=1;
    clrscr();
    num:cout<<"\nEnter a number";
    cin>>n;
    if(n<=0)
    {
      cout<<"Invalid Number Enter again";
      goto num;
    }
    while(i<=10)
    {
        cout<<n*i<<endl;
        i++;
    }
}

Program 3

// Program for table of number
#include<iostream>
using namespace std;
#define clrscr() system("cls")
int main()
{
    char ch='A';
    while(ch<='Z')
    {
        cout<<ch<<endl;
        ch++;
    }
    // int n,i=1;
    // clrscr();
    // while(i<=10)
    // {
    //     cout<<i*i<<endl;
    //     i++;
    // }
    return 0;

}