Practice Program






  • Program of calculating sum of n natural numbers

    • Solution: through for loop 
    void main()
{
    int n,i,sum = 0;;
    printf("Sum of how many numbers: ");
    scanf("%d",&n);
    
    //at every iteration we are assigning 
    //(current_value + i ) to new value of sum. 
    for(i=1;i<=n;i++)
    {
        sum = sum+i;
    }
    
    
    printf("Sum of first %d natural numbers are %d",n,sum);
   

}

    Output1
    Sum of how many numbers:5

    Sum of first 5 natural numbers are 15.
    Output2
    Sum of how many numbers:10

    Sum of first 10 natural numbers are 55.
    Output3
    Sum of how many numbers:15

    Sum of first 15 natural numbers are 120.




    Solution : through while loop 
    void main()
{
    int n,i,sum = 0;;
    printf("Sum of how many numbers: ");
    scanf("%d",&n);
      i=1;
    //at every iteration we are assigning
    //(current_value + i ) to new value of sum.
    while(i<=n)
    {
        sum = sum+i;
        i++;
    }


    printf("Sum of first %d natural numbers are %d",n,sum);


}





    Solution: from do-while loop 
    void main()
{
    int n,i,sum = 0;;
    printf("Sum of how many numbers: ");
    scanf("%d",&n);
      i=1;
    //at every iteration we are assigning
    //(current_value + i ) to new value of sum.
    do
    {
        sum = sum+i;
        i++;
    }while(i<=n)


    printf("Sum of first %d natural numbers are %d",n,sum);


}




    defining a function 'sum' which will return sum of n numbers.

    int sum(int n)
{
    int i,sum=0;

     //at every iteration we are assigning
    //(current_value + i ) to new value of sum.
    for(i=1;i<=n;i++)
    {
        sum = sum+i;
    }
    return sum;
}

    Using above defined function 'Sum':
    void main()
{
    int n,result;
    printf("How many  numbers of sum you want: ");
    scanf("%d",&n);


   result  = sum(5);


   printf("Sum of first %d numbers are %d",n,result);



}

    Output1
    Sum of how many numbers:5

    Sum of first 5 natural numbers are 15.

    Using above defined function 'Sum':
    void main()
{
    int n,result;
    printf("How many  numbers of sum you want: ");
    scanf("%d",&n);


   result  = sum(10);


   printf("Sum of first %d numbers are %d",n,result);



}

    Output2
    Sum of how many numbers:10

    Sum of first 10 natural numbers are 55.

    Using above defined function 'Sum':
    void main()
{
    int n,result;
    printf("How many  numbers of sum you want: ");
    scanf("%d",&n);


   result  = sum(15);


   printf("Sum of first %d numbers are %d",n,result);



}

    Output3
    Sum of how many numbers:15

    Sum of first 15 natural numbers are 120.