Matrix Chain Multiplication

OPTIMIZED MEMOIZATION / BOTTOM DOWN DP

int static t[101][101];
class Solution{
public:
    int mcm(int arr[],int i,int j){
        if(i>=j) return 0;
        if(t[i][j]!=-1) return t[i][j];
        int ans=INT_MAX;
        for(int k=i;k<j;k++){
            int l,r;
            if(t[i][k]!=-1) l=t[i][k];
            else{
                l=mcm(arr,i,k);
                t[i][k]=l;
            }
            if(t[k+1][j]!=-1) r=t[k+1][j];
            else{
                r=mcm(arr,k+1,j);
                t[k+1][j]=r;
            }
            int temp=(arr[i-1]*arr[k]*arr[j])+l+r;
            ans=min(temp,ans);
        }
        return ans;
    }
    int matrixMultiplication(int N, int arr[])
    {
        memset(t,-1,sizeof(t));
        return mcm(arr,1,N-1);
    }
};