Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	p := make([]int, N+1)
	dp := make([][]int, N+1)
	for i, _ := range dp {
		dp[i] = make([]int, N+1)
	}
	for i := 0; i < N; i++ {
		p[i] = sc.nextInt()
		p[i+1] = sc.nextInt()
	}
	for i := 1; i <= N; i++ {
		dp[i][i] = 0
	}
	for l := 2; l <= N; l++ {
		for i := 1; i <= N-l+1; i++ {
			j := i + l - 1
			dp[i][j] = 1 << 60
			for k := i; k <= j-1; k++ {
				dp[i][j] = min(dp[i][j], dp[i][k]+dp[k+1][j]+p[i-1]*p[k]*p[j])
			}
		}
	}

	fmt.Fprintln(wtr, dp[1][N])
	wtr.Flush()
}

Python: N = int(input())
P = []
for i in range(N):
    r, c = map(int, input().split())
    if i == 0:
        P.append(r)
    P.append(c)


def matrix_chain():
    dp = [[None for j in range(N+1)] for i in range(N+1)]
    for i in range(1, N+1):
        dp[i][i] = 0

    for l in range(2, N+1):
        for i in range(1, N-l+2):
            j = i + l - 1
            dp[i][j] = 1000000000000000
            for k in range(i, j):
                dp[i][j] = min(dp[i][j], dp[i][k]+dp[k+1][j]+P[i-1]*P[k]*P[j])

    return dp[1][N]


def main():
    print(matrix_chain())


if __name__ == '__main__':
    main()

Python: #!/usr/bin/env python
from __future__ import division, print_function
from sys import stdin


def main():
    num_mat = int(stdin.readline())
    r = [int(s) for s in stdin.readline().split()]
    for _ in range(num_mat-1):
        _, row = (int(s) for s in stdin.readline().split())
        r.append(row)

    if num_mat < 2:
        print(0)
        return
    elif num_mat < 3:
        print(r[0]*r[1]*r[2])
        return

    M = []
    M.append([0] * num_mat)
    M.append([r[i]*r[i+1]*r[i+2] for i in range(len(M[-1])-1)])

    for i in range(2, num_mat):
        N = []
        for j in range(num_mat-i):
            N.append(min(M[k][j]+M[i-1-k][1+j+k]+r[j]*r[1+j+k]*r[i+1+j]
                         for k in range(i)))
        M.append(N)
    print(M[-1][0])


main()

Python: # https://onlinejudge.u-aizu.ac.jp/courses/lesson/1/ALDS1/10/ALDS1_10_B
# 普通に難しい
# アイデアは写真の解説を参照

# データの入力
N = int(input())

for i in range(N):
    if i == 0:
        P = list(map(int, input().split()))
        continue
    P.append(int(input().split()[1]))

# dpテーブルの用意 minを取るときはinf埋めしておくと処理が楽になるしバグが見つかりやすい
INF = 2**32-1
dp = [[INF]*N for _ in range(N)]

# dpテーブルの初期化
# 対角成分0
for ij in range(N):
    dp[ij][ij] = 0

# dpの更新 どう更新しているのか、なんでこう更新するのかは写真を参照
for l in range(1, N):  # lは対角成分からいくつ離れているか (なん個行列をかけるかという解釈も可)
    for i in range(N):
        j = i+l
        if j >= N:
            continue
        for k in range(i, j):
            dp[i][j] = min(dp[i][k] + dp[k+1][j] + P[i]
                           * P[j+1]*P[k+1], dp[i][j])
# from pprint import pprint
# pprint(dp)
print(dp[0][-1])

Python: import sys
sys.setrecursionlimit(10**7)
debug = False

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 = [[0 for i in range(n)] for i in range(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: N = int(input())

P = []
for i in range(N):
    if i == 0:
        P = list(map(int, input().split()))
        continue
    P.append(int(input().split()[1]))

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

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

for l in range(1, N):  
    for i in range(N):
        j = i+l
        if j < N:
            for k in range(i, j): 
                dp[i][j] = min(dp[i][k] + dp[k+1][j] + P[i]*P[j+1]*P[k+1], dp[i][j])

print(dp[0][-1])

Python: N = int(input())
R = [0]*N
C = [0]*N
for i in range(N):
    R[i], C[i] = map(int, input().split())

INF = 10**18
dp = [[INF]*N for i in range(N)]
for i in range(N):
    dp[i][i] = 0
for l in range(1, N):
    for i in range(N-l):
        a0 = R[i]
        c0 = C[i+l]
        dp[i][i+l] = min(a0*C[j]*c0 + dp[i][j] + dp[j+1][i+l] for j in range(i, i+l))
print(dp[0][N-1])

Python: import sys

n = int(sys.stdin.readline())

m = list(map(int, sys.stdin.readline().split()))
for _ in range(n-1):
    _, a = sys.stdin.readline().split()
    m.append(int(a))

c = [[-1 for _ in range(n)] for _ in range(n)]

def val(a, b):
    if a==b: return 0
    if c[a][b]>0: return c[a][b]
    c[a][b]=val(a+1,b)+m[a-1]*m[a]*m[b]
    for k in range(a+1, b):
        v=val(a,k)+val(k+1,b)+m[a-1]*m[k]*m[b]
        if c[a][b]>v: c[a][b]=v
    return c[a][b]

print(val(0, n-1))