Go: package main

/*
連鎖行列積
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"math"
	"os"
	"strconv"
	"strings"
)

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

type mem *[][]int

func main() {
	scanner := makeScanner(1024)
	n := eGetInt(scanner)
	p := make([]int, n+1)
	for i := 0; i < n; i++ {
		rowcol := eGetInts(scanner)
		p[i] = rowcol[0]
		p[i+1] = rowcol[1]
	}
	m := make([][]int, n)
	for i := 0; i < n; i++ {
		m[i] = make([]int, n)
	}
	// 初期値の格納
	for i := 0; i < n; i++ {
		for j := i; j < n; j++ {
			if i == j {
				m[i][j] = 0 //  同じ行列へのコストは当然0
			} else {
				m[i][j] = math.MaxInt64
			}
		}
	}

	// num : 行列の数. num == 1の場合は初期値0を格納ずみ
	for num := 2; num <= n; num++ {
		// s : スタート行列番号
		for s := 0; s+num <= n; s++ {
			// t : 終了行列番号
			t := s + num - 1
			// k : 仕切
			for k := s; k < t; k++ {
				m[s][t] = min(m[s][t], m[s][k]+m[k+1][t]+p[s]*p[k+1]*p[t+1])
			}
		}
	}
	fmt.Println(m[0][n-1])
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}

// func min(a []int) int {
// 	m := a[0]
// 	for _, v := range a {
// 		if v < m {
// 			m = v
// 		}
// 	}
// 	return m
// }

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

Python: #!/usr/bin/env python3
# -*- coding: utf-8 -*-

import sys
import re
import math
import collections
import itertools
import functools
import logging

logging.basicConfig(level=logging.DEBUG, format="DBG: %(message)s")

def dbg(msg, *args, **kwargs):
    logging.debug(msg, *args, **kwargs)

Mat = collections.namedtuple("Mat", "r c")

def mat_mul(ms):
    return Mat(ms[0].r, ms[-1].c)

def cost(m1, m2):
    return m1.r * m1.c * m2.c

def solve(n, ms):
    if n == 1: return 0

    dp = {}
    for i in range(n):
        dp[(i,i)] = 0

    for l in range(2, n+1):
        for i in range(n-l+1):
            cost_min = math.inf
            for j in range(l-1):
                dbg("l, i, j: %d %d %d", l, i, j)
                m_lhs = mat_mul(ms[i:i+j+1])
                m_rhs = mat_mul(ms[i+j+1:i+l])
                dbg("m_lhs, m_rhs: %r %r", m_lhs, m_rhs)
                cost_lhs = dp[(i,i+j)]
                cost_rhs = dp[(i+j+1,i+l-1)]
                dbg("cost_lhs, cost_rhs: %d %d", cost_lhs, cost_rhs)
                cost_mul = cost(m_lhs, m_rhs)
                dbg("cost_mul: %d", cost_mul)
                cost_now = cost_mul + cost_lhs + cost_rhs
                dbg("cost_now: %d", cost_now)
                if cost_min > cost_now:
                    cost_min = cost_now
            dp[(i,i+l-1)] = cost_min

    dbg(dp)
    return dp[(0,n-1)]

def main():
    n = int(input())

    ms = []
    for _ in range(n):
        r,c = map(int, input().split())
        ms.append(Mat(r,c))

    print(solve(n, ms))

if __name__ == "__main__": main()

Python: # -*- coding: utf-8 -*-
import functools
INF = 10**9
n = int(input())
p = list(map(int, input().split()))
for i in range(n - 1):
    p.append(int(input().split()[1]))


@functools.lru_cache(maxsize=None)
def matrix_chain_multiplication(i, j):
    if i == j:
        return 0

    tmp = INF
    for k in range(i, j):
        tmp = min(
            tmp,
            matrix_chain_multiplication(i, k) +
            matrix_chain_multiplication(k + 1, j) + p[i - 1] * p[k] * p[j])
    return tmp


print(matrix_chain_multiplication(0, n - 1))

Python: import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")

def main():
    def get_cost(l,r):
        if r-l==1:return 0
        if r-l==2:return rc[l][0]*rc[r-1][0]*rc[r-1][1]
        if cost[l][r]!=-1:
            return cost[l][r]
        res=cost[l][r]=min(get_cost(l,m)+get_cost(m,r)
                           +rc[l][0]*rc[m][0]*rc[r-1][1] for m in range(l+1,r))
        return res

    n=int(input())
    rc=[list(map(int,input().split())) for _ in range(n)]
    cost=[[-1]*(n+1) for _ in range(n)]
    print(get_cost(0,n))

main()

Python: n = int(input())
p = [item for sublist in [[int(input().split()[1])] if i != 0 else list(map(int, input().split())) for i in range(n)] for item in sublist]

def memolize(f):
    cache = {}

    def helper(x, y):
        if (x, y) not in cache:
            cache[(x, y)] = f(x, y)
        return cache[(x, y)]
    return helper

@memolize
def calcMatrixOrder(i, j):
    if i == j :
        return 0
    return min([calcMatrixOrder(i, k) + calcMatrixOrder(k + 1, j) + p[i]*p[k+1]*p[j + 1] for k in range(i, j)])

print(calcMatrixOrder(0, n - 1))

Python: global memo

def find_memo(m,l):#memoのm行l列の値を返す.data
                            #data[l]から続くm+1個の要素からなる部分リスト
    if(memo[m][l]!=0):
        return memo[m][l]
    
    if(m<2):
        return memo[m][l]
    

    tmp_min=999999999
    for i in range(1,m):
        left=find_memo(i,l)
        right=find_memo(m-i,l+i)
        middle=memo[0][l]*memo[0][l+i]*memo[0][l+m]
        if(left + right + middle< tmp_min):
            tmp_min = left + right + middle
    memo[m][l]=tmp_min
    return tmp_min




tmp_min=9999999999
n=int(input())
memo=[[0]*(n+1-i) for i in range(n+1)]#memo[i][j]はdata[j]から続くi+1個の要素からなる部分リストの最小計算コストを表す

memo[0][0],memo[0][1]=map(int,input().split())
for i in range(2,n+1):
    dummy,memo[0][i]= map(int,input().split())

for i in range(n-1):
    memo[2][i] = memo[0][i]*memo[0][i+1]*memo[0][i+2]

print(find_memo(n,0))

Python: def matrixChainMultiplication(n):
    # for i in range(1, n+1):
    #     m[i][i] = 0
    for l in range(2, n+1):
        for i in range(1, n-l+1+1):
            j = i + l - 1
            m[i][j] = 999999999
            for k in range(i, j):
                m[i][j] = min(m[i][j], m[i][k] + m[k+1][j] + p[i-1]*p[k]*p[j])
    return m[1][n]

n = int(input())
squareM = [input().split(" ") for _ in range(n)]
p = [int(squareM[i][0]) for i in range(n)]
p.append(int(squareM[n-1][1]))
m = [[0]*(n+1) for _ in range(n+1)]
print(matrixChainMultiplication(n))