Matrix chain multiplication

On geeksforgeeks website I ran into the problem of <strong> multiplying a matrix chain .

There is a recursive solution for this problem, but the code is hard for me to understand. Actually, I am having problems with a certain line of code.

First of all, this is the code:

#include <stdio.h>
#include <limits.h>

//Matrix Ai has dimension p[i-1] x p[i] for i = 1...n
int MatrixChainOrder(int p[], int i, int j)
{
    if(i == j)
        return 0;
    int k, min = INT_MAX, count;

    for(k=i; k < j; k++) {
        count = MatrixChainOrder(p,i,k) + MatrixChainOrder(p,k+1,j) + p[i-1]*p[k]*p[j];

    if(count < min)
        min = count;
    }

    return min;
}

int main() {

    int arr[] = {1, 2, 3, 4, 3};
    int n = sizeof(arr)/sizeof(arr[0]);

    printf("Minimum number of multiplications is %d ", MatrixChainOrder(arr, 1, n-1));

    getchar();
    return 0;
}

      

        
        
        
      

    

Matrices: A = 1x2, B = 2x3, C = 3x4, D = 4x3

The line that is giving me some problem is this

count = MatrixChainOrder(p,i,k) + MatrixChainOrder(p,k+1,j) + p[i-1]*p[k]*p[j];

      

        
        
        
      

    

At the beginning of the for loop, i = 1

and j = 4

. So will evaluate as , which is obviously wrong, because matrix A can only be multiplied by B. I ran the code and nothing seems there was no result here because there was no result for the result, and also the same problem for the case ... p[i-1]*p[k]*p[j]

p[0]*p[1]*p[4] = 1x2x3

p[i-1]*p[k]*p[j]

i = 2, j = 4

Can someone enlighten me? I would be grateful if you could explain recursion to me in this code. I mean the way and the way it works.