Given an integer N the task is to print the F(N)th term in C++

October 14, 2022

Print F(N)th term in C++

 

Here, in this page we will discuss the program to print the F(N)th term in C++ Programming Language.  A function f is defined as follows F(N)= (1) +(2*3) + (4*5*6) … N. We are given with an integer N and we need to print the F(N)th term.

Example :

  • Input : 4
  • Output : 5167
  • Explanation : 1 + (2*3) + (4*5*6) + (7*8*9*10) = 5167.
Print F(N)th term in C++

Method 1 (Using Recursion) :

  • Create a recursive function say term(int calculated, int current, int N)
  • Declare a variable cur to hold the product of the terms and initialize it with 1.
  • Base condition will be if(current == N+1) then, return 0. Here, current denotes the current term of the series.
  • Now, run a loop to calculate the product of terms till current.
  • Set i= calculate. Termination condition of the loop will be i>= calculated + current.
  • Inside loop set cur *= i
  • After execution of loop return cur + term(i, current+1, N)
print f(n)th term

Code to Print F(N)th term in C++

Run 
#include<bits/stdc++.h>
using namespace std;

// Recursive function 
int term(int calculated, int current, int N) 
{
    int i, cur = 1;

    // Base Condition
    if (current == N + 1) 
       return 0;

    // product of terms till current
    for (i = calculated; i < calculated + current; i++)
        cur *= i;

     return cur + term(i, current + 1, N); 
}

// Driver Code
int main()
{
    int N = 3;

    cout<<term(1, 1, N);

    return 0;
}
Output :

127

Method 2 (Using Loop) :

  • Create a function say term(int calculated, int current, int N) to calculate the required N-th term.
  • Declare a variable result = 0.
  • Run a while loop till current != N+1.
  • Inside while loop declare a variable cur to hold the product of the terms and initialize it with 1.
  • Now, run a loop to calculate the product of terms till current.
  • Set i= calculate. Termination condition of the loop will be i>= calculated + current.
  • Inside for loop set cur *= i.
  • After execution of for loop set calculated = i, result += curr and increment current value by 1.
  • After the execution of while loop return result.

Code to Print F(N)th term in C++

Run 
#include<bits/stdc++.h>
using namespace std;

//Function to calculate N-th term
int term(int calculated, int current, int N) 
{
  int i, result = 0;

  while(current != N + 1){ 

    int cur = 1;
    // product of terms till current
    for (i = calculated; i < calculated + current; i++)
       cur *= i; 

    calculated=i;
    result += cur;
    current++;
  }
   
   return result; 
}

// Driver Code
int main()
{
  int N = 3;

  cout<<term(1, 1, N);

  return 0;
}
Output :

127

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While loop in C

3 comments on “Given an integer N the task is to print the F(N)th term in C++”


  • Yash

    num=4
    sum=0
    for i in range(0,num+1):
    sum=sum+i
    out=0
    def fn(sum,num):
    if num==1:
    return 1
    else:
    total=1
    for i in range(sum-num+1,sum+1):
    total=total*i
    return total+fn(sum-num,num-1)
    print(fn(sum,num))


  • amanbajpai5734

    C++ Code :=>

    #include
    using namespace std;
    int main()
    {
    int n,product,result=0;
    cout<>n;
    int k=1;
    for(int i=1;i<=n;i++)
    {
    product=1;
    for(int j=0;j<i;j++)
    {
    if(i==1)
    product=1;
    else{
    product=product*k;
    }
    k++;
    }
    result=result+product;
    }
    cout<<result;
    }