Formula

Program

nCr & nPr program ?


#include 

long factorial(int);
long find_ncr(int, int);
long find_npr(int, int);

main() {

  int n, r;
  long ncr, npr;

  printf("Enter the value of n and r\n");
  scanf("%d%d", &n, &r);

  ncr = find_ncr(n, r);
  npr = find_npr(n, r);

  printf("%dC%d = %ld\n", n, r, ncr);
  printf("%dP%d = %ld\n", n, r, npr);

  return 0;
}

long find_ncr(int n, int r) {

  long result;

  result = factorial(n) / (factorial(r) * factorial(n - r));

  return result;
}

long find_npr(int n, int r) {

  long result;

  result = factorial(n) / factorial(n - r);

  return result;
}

long factorial(int n) {

  int c;
  long result = 1;

  for (c = 1; c <= n; c++)
    result = result * c;

  return (result);
}

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