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: MAX_R = 100
MAX_C = 100
n = int(input())
mat_list = [list(map(int, input().split())) for _ in range(n)]
dp = [[-1] * (MAX_C + 1) for _ in range(MAX_R + 1)]

def get_min(i, j):
    ans = float('inf')
    if dp[i][j] != -1:
        return dp[i][j]
    if i == j:
        ans = 0
    else:
        for k in range(i, j):
            p = mat_list[i][0]
            q = mat_list[k][1]
            r = mat_list[j][1]
            tmp = get_min(i, k) + get_min(k+1, j) + p*q*r
            if tmp < ans:
                ans = tmp
    dp[i][j] = ans
    return ans

print(get_min(0, n-1))

Python: import sys
sys.setrecursionlimit(10**7)
debug = False
import numpy as np
def dprint(*objects):
    if debug == True:
        print(*objects)

# n = int(input())
# a, b = map(int, input().split())
# int_list = list(map(int, input().split()))
# l = list(input().split())



def solve():
    n = int(input())
    mat_list = []
    for i in range(n):
        mat_list.append(list(map(int, input().split())))
    dprint(mat_list)

    # 掛け始めのidxと掛け終わりのidxをi, jとし、計算回数を持つメモ
    memo = np.zeros(shape=(n, n))

    def calc(start, end):
        dprint("*", start, end)
        # 1つの行列なら0
        if end == start:
            return 0

        # メモがあれば返す
        if memo[start][end] != 0:
            return memo[start][end]

        # 2つの行列なら、答えを計算しメモ追記
        if end - start == 1:
            cost = mat_list[start][0] * mat_list[start][1] * mat_list[end][1]
            memo[start][end] = cost
            dprint(start, end, cost)
            return cost

        # 3つ以上なら、再帰
        min_cost = -1
        if end - start >= 2:
            for right_start in range(start+1, end+1):
                left = calc(start, right_start-1)
                right = calc(right_start, end)
                cost = left + right + mat_list[start][0] * mat_list[right_start][0] * mat_list[end][1]
                if min_cost == -1 or min_cost > cost:
                    min_cost = cost
                dprint(start, end, right_start, min_cost, cost)

        memo[start][end] = min_cost
        return min_cost

    ans = calc(0, n-1)
    dprint(memo)
    print(int(ans))

solve()

Python: #coding:utf-8
import numpy as np

n = int(input())
m = [[0 for i in range(n)] for j in range(n)]
m = np.array(m)
p = []
for i in range(n):
    p1,p2 = map(int,input().split())
    if i == 0:
        p.append(p1)
    p.append(p2)

def matrixChainMultiplication():
    for i in range(n):
        m[i,i] = 0

    for l in range(2,n+1):
        for i in range(0,n-l+1):
            j = i + l - 1
            m[i,j] = 1000000
            for k in range(i,j):
                m[i,j] = min(m[i,j], m[i,k] + m[k+1,j] + p[i] * p[k+1] * p[j+1])
matrixChainMultiplication()
print(m[0,n-1])

Python: n = int(input())

r = [0] * n
c = [0] * n

for i in range(n):
    r[i], c[i] = map(int, input().split())

dp = [[float("inf")] * n for _ in range(n)]

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

for gap in range(1, n):
    for s in range(n):
        e = s + gap
        if e >= n:
            continue
        for k in range(s, e):
            dp[s][e] = min(dp[s][e], dp[s][k] + dp[k + 1][e] + r[s] * c[k] * c[e])

print(dp[0][n - 1])

Python: def matrixChainMultiplication(M):
    # P ??????
    n = len(M)
    P = [M[0][0]]
    P += [M[i][1] for i in range(n)]
    # ?¨???¶?????? m ??????
    m = [[[] for _ in range(n + 1)] for _ in range(n + 1)]
    for i in range(n + 1):
            m[i][i] = 0

    # l???????±???¨?????????????????°
    for l in range(2, n + 1):
        for i in range(1, n - l + 2):
            j = i + l - 1
            m[i][j] = 9999999999999999
            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]


if __name__ == '__main__':
    n = int(input())
    M = [list(map(int, input().split())) for _ in range(n)]
    print(matrixChainMultiplication(M))

Python: n = input().split()

nele = int(n[0])
list = range(1,nele+1)

nrow = {}
ncol = {}
for i in list:
	nrow[i] = int(n[i*2-1])
	ncol[i] = int(n[i*2])

#print(nrow, ncol)


min = -1
cur = -1
route = []
done = []

for i in list:
	route.append(0)

#print(route)

depth = -1
min = -1
def tansaku(prev):
	
	global depth
	depth += 1
	
	global nrow
	global ncol
	global min
	global route
	
	done = route[:]
	
	for i in list:
#		print(depth, i, route, done)
		
		if i in done:
			continue
		
		next = i
		done.append(next)
		
		if depth == 0:
			route[depth] = next
			tmp = 0
			min = tansaku(tmp)
			continue
		
		tmp = prev + nrow[route[depth-1]] * ncol[next]
#		print(tmp)
		
		if tmp > min and min != -1:
#			print("aaa")
			continue
		else:
			route[depth] = next
			if depth >= nele-1:
				print("bbb")
				min = tmp
			else:
#				print("ccc")
				min = tansaku(tmp)
	
	depth -= 1
	route[depth] = 0
#	print("min:", min)
	return min

min = tansaku(0)

print(min)