Answer to Question #217580 in C++ for Akash

Question

given a number of mangoes and number of persons. Find the number of ways to distribute identical mangoes among identical persons in c++

Answer 1

#include <bits/stdc++.h>
using namespace std;
 
// function used to generate binomial coefficient
// time complexity O(m)
int binomial_coefficient(int n, int m)
{
    int res = 1;
 
    if (m > n - m)
        m = n - m;
 
    for (int i = 0; i < m; ++i) {
        res *= (n - i);
        res /= (i + 1);
    }
 
    return res;
}
 
// helper function for generating no of ways
// to distribute m mangoes amongst n people
int calculate_ways(int m, int n)
{
    // not enough mangoes to be distributed
    if (m < n)
        return 0;
     
    // ways  -> (n+m-1)C(n-1)
    int ways = binomial_coefficient(n + m - 1, n - 1);
    return ways;
}
 
// Driver function
int main()
{
    // m represents number of mangoes
    // n represents number of people
    int m = 7, n = 5;
 
    int result = calculate_ways(m, n);
    printf("%d\n", result);
 
    return 0;
}