Description
Get the input from the user for the value of n and then find the sum of first n natural numbers.
e.g. let the n value = 5
then first 5 natural numbers are 1,2,3,4,5 for which we need to find the sum
Therefore sum of first 5 natural numbers is 1+2+3+4+5 = 15
Input
4
Output
10
C program Method 1
#include <stdio.h>
int main()
{
int num,sum=0;
printf("Enter the number");
scanf("%d",&num);
for(int i=1;i<=num;i++)
sum=sum+i;
printf("%d",sum);
return 0;
}
C program Method 2
#include<stdio.h>
int Sum(int n)
{
if (n!=0)
return n + Sum(n-1);
else
return 0;
}
int main()
{
int num,sum=0;
printf("Enter the number: ");
scanf("%d",&num);
sum=Sum(num);
printf("%d",sum);
return 0;
}
C++ Program Method 1
#include <iostream>
using namespace std;
int main()
{
int num,sum=0;
cout<<"Enter the number: ";
cin>>num;
for(int i=1;i<=num;i++)
sum=sum+i;
cout<<sum;
return 0;
}
C++ Program Method 2
#include <iostream>
using namespace std;
int Sum(int n)
{
if (n!=0)
return n + Sum(n-1);
else
return 0;
}
int main()
{
int num,sum=0;
cout<<"Enter the number: ";
cin>>num;
cout<<Sum(num);
return 0;
}
Java Program
import java.util.Scanner;
public class Main
{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num = sc.nextInt();
int sum= 0;
for(int i=0;i<=num;i++)
sum = sum + i;
System.out.print(sum);
}
}
Python Program Method 1
num=int(input("Enter a number: "))
Sum=0
for i in range(1,num+1):
Sum=Sum+i
print(Sum)
Python Program Method 2
def Sum(num):
if num!=0:
return num + Sum(num-1)
else:
return 0
num=int(input("Enter a number: "))
value=Sum(num)
print(value)