add new dp code

Author: msdeep14

a.out

@@ -0,0 +1,43 @@
+// https://www.geeksforgeeks.org/dynamic-programming-set-8-matrix-chain-multiplication/
+#include <bits/stdc++.h>
+using namespace std;
+
+int matrixOrder(int p[], int i, int j){
+	if(i == j) return 0;
+	int k, minn = INT_MAX, count;
+
+	for(int k=i;k<j;k++){
+		count = matrixOrder(p,i,k) + matrixOrder(p,k+1,j) + p[i-1]*p[k]*p[j];
+		if(count < minn)
+			minn = count;
+	}
+	return minn;
+}
+
+int matrixOrderDP(int p[], int n){
+	int m[n+1][n+1];
+	for(int i=1;i<n;i++)
+		m[i][i] = 0;
+
+	for(int l=2;l<n;l++){
+		for(int i=1;i<n-l+1;i++){
+			int j=i+l-1;
+			m[i][j] = INT_MAX;
+			for(int k=i;k<j;k++){
+				int q = m[i][k] + m[k+1][j] + p[i-1]*p[k]*p[j];
+				if(q < m[i][j])
+					m[i][j] = q;
+			}	
+		}
+	}
+	return m[1][n-1];
+}
+
+int main(){
+	int p[] = {1,2,3,4};
+	int n = sizeof(p)/sizeof(p[0]);
+	// int res = matrixOrder(p, 1, n-1);
+	int res = matrixOrderDP(p,n);
+	cout << res << endl;
+	return 0;
+}