In this post, we will learn **how to calculate the value of nCr using C** Programming language.

**nCr** means if you are given **“n”** different items and you have to choose **“r”** items from it, then** nCr** gives the total number of ways possible to choose the items.

The Combination formula can also be represented as **C(n, r)**. The formula to compute **nCr is = nCr = n! / (r!(n-r)!)**.

We will be using the same formula in our program to calculate the value of **nCr**.

So, without further ado, let’s begin the tutorial.

**C Program To Calculate The Value of nCr**

// C Program To Calculate The Value of nCr #include <stdio.h> int fact(int n){ int i, a = 1; for (i = 1; i <= n; i++){ a = a * i; } return a; } int main(){ int n, r, nCr; // Asking for Input printf("Enter the value of n: "); scanf("%d", &n); printf("Enter the value of r: "); scanf("%d", &r); nCr = fact(n) / (fact(r) * fact(n - r)); printf("The Value of C(%d, %d) is %d.", n, r, nCr); return 0; }

**Output**

```
Enter the value of n: 7
Enter the value of r: 4
The Value of C(7, 4) is 35.
```

**How Does This Program Work ?**

**int fact(int n){
int i, a = 1;
for (i = 1; i <= n; i++){
a = a * i;
}
return a;
}**

In this program, we have defined a custom function named as **fact**.

** int n, r, nCr;**

We have declared three int data type variables named as **n**, **r** and **nCr**.

` `** // Asking for Input
printf("Enter the value of n: ");
scanf("%d", &n);
printf("Enter the value of r: ");
scanf("%d", &r);**

Then, the user is asked to enter the value of n and r.

** nCr = fact(n) / (fact(r) * fact(n - r));
printf("The Value of C(%d, %d) is %d.", n, r, nCr);**

We used the combination formula to calculate the value of **nCr**. Finally, we print the result using** printf()** function.

**Conclusion**

I hope after going through this post, you understand **how to calculate the value of nCr using C** Programming language.

If you have any doubt regarding the program, feel free to contact us in the Comment section. We will be delighted to help you.

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