#include #include #include using namespace std; // Matrix Ai has dimension p[i-1] x p[i] for i = 1..n int MatrixChainOrder(int p[], int n) { /* For simplicity of the program, one extra row and one extra column are allocated in m[][]. 0th row and 0th column of m[][] are not used */ int m[n][n]; int s[n][n]; int i, j, k, L, q; /* m[i,j] = Minimum number of scalar multiplications needed to compute the matrix A[i]A[i+1]...A[j] = A[i..j] where dimention of A[i] is p[i-1] x p[i] */ // cost is zero when multiplying one matrix. for (i = 1; i < n; i++) m[i][i] = 0; // L is chain length. for (L = 2; L < n; L++) { for (i = 1; i <= n - L + 1; i++) { j = i + L - 1; m[i][j] = INT_MAX; for (k = i; k <= j - 1; k++) { // q = cost/scalar multiplications q = m[i][k] + m[k + 1][j] + p[i - 1] * p[k] * p[j]; if (q < m[i][j]) { m[i][j] = q; s[i][j] = k; } } } } return m[1][n - 1]; } int main() { cout << "Enter the array p[], which represents the chain of matrices such that the ith matrix Ai is of dimension p[i-1] x p[i]"; cout << "Enter the total length:"; int n; cin >> n; int array[n]; cout << "Enter the dimensions: "; for (int var = 0; var < n; ++var) { cin >> array[var]; } cout << "Minimum number of multiplications is: " << MatrixChainOrder(array, n); return 0; } /* Enter the array p[], which represents the chain of matrices such that the ith matrix Ai is of dimension p[i-1] x p[i]Enter the total length:4 Enter the dimensions: 2 4 3 5 Minimum number of multiplications is: 54