Go: package main

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

type Matrix struct {
	r int // num of row
	c int // num of column
}

type Range struct {
	start int // index, inclusive
	end   int // index, inclusive
}

func calcMultiplication(x, y Matrix) (Matrix, int) {
	if x.c != y.r {
		panic("cannnot calculate")
	}
	return Matrix{x.r, y.c}, x.r * y.c * x.c
}

func calcMinMatrixChainMultiplication(matrices []Matrix, r Range, memo map[Range]int) (Matrix, int) {
	if v, ok := memo[r]; ok {
		return Matrix{matrices[0].r, matrices[len(matrices)-1].c}, v
	}
	if len(matrices) == 0 {
		panic("must not be empty")
	} else if len(matrices) == 1 {
		return matrices[0], 0
	}

	var minCount int = math.MaxInt32

	for i := 0; i < len(matrices)-1; i++ {
		formerMatrices := matrices[:i+1]
		latterMatrices := matrices[i+1:]
		matF, countF := calcMinMatrixChainMultiplication(formerMatrices, Range{0, i}, memo)
		matL, countL := calcMinMatrixChainMultiplication(latterMatrices, Range{i + 1, len(matrices) - 1}, memo)
		_, countFL := calcMultiplication(matF, matL)
		count := countF + countL + countFL
		if count < minCount {
			minCount = count
		}
	}
	memo[r] = minCount
	return Matrix{matrices[0].r, matrices[len(matrices)-1].c}, minCount
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n, _ := nextInt(sc)
	matrices := make([]Matrix, n)
	for i := 0; i < n; i++ {
		r, _ := nextInt(sc)
		c, _ := nextInt(sc)
		matrices[i] = Matrix{r, c}
	}
	memo := make(map[Range]int)
	_, resultCount := calcMinMatrixChainMultiplication(matrices, Range{0, len(matrices) - 1}, memo)
	fmt.Println(resultCount)
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

Python: import sys
from functools import lru_cache
input = sys.stdin.readline
sys.setrecursionlimit(2 * 10**6)


def inpl():
    return list(map(int, input().split()))


def main():
    @lru_cache(maxsize=None)
    def recur(i, j):
        # print(i, j)
        if i == j:
            return 0
        for k in range(i, j):
            c = recur(i, k) + recur(k + 1, j) + P[i] * P[k + 1] * P[j + 1]
            if c < cost[i][j]:
                cost[i][j] = c
        return cost[i][j]

    N = int(input())
    RC = [inpl() for _ in range(N)]
    cost = [[float('inf')] * (N + 1) for a in range(N + 1)]
    P = [0] * (N + 1)
    for i, rc in enumerate(RC):
        P[i] = rc[0]
    P[N] = RC[N - 1][1]

    print(recur(0, N - 1))


if __name__ == '__main__':
    main()

Python: import sys
import itertools

n = int(sys.stdin.readline())
MM = [list(map(int, sys.stdin.readline().split())) for _ in range(n)]

amin=1000000000000
for t in itertools.permutations(range(n-1)):
    mm=[m[:] for m in MM]
    o = list(t)
    ans=0
    for _ in range(n-1):
        i = o.pop(0)
        ans += mm[i][0]*mm[i+1][1]*mm[i][1]

        mm[i][1] = mm[i+1][1]
        mm.pop(i+1)
        
        for j in range(len(o)):
            if o[j]>i: o[j] -=1

    if amin>ans: amin=ans


print(amin)

Python: N = int(input())
P = []
for i in range(N):
	ta,tb = map(int ,input().split())
	if i == N-1:
		P.append(ta)
		P.append(tb)
	else:
		P.append(ta)
inf = float('inf')
dp = [[inf] * N for _ in range(N)]
for i in range(N):
	if i == N-1:
		dp[i][i] = 0
	else:
		dp[i][i] = 0
		dp[i][i+1] = P[i]*P[i+1]*P[i+2]

for right in range(2,N):
	for i in range(N):
		j = i + right
		if j > N-1:
			break

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

		

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

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)

Python: import sys

input = sys.stdin.readline
INF = float("inf")


def main():
    n = int(input())
    r = [None] * n
    c = [None] * n
    for i in range(n):
        r[i], c[i] = map(int, input().split())

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

    for width in range(2, n + 1):
        for i in range(n - width + 1):
            j = i + width - 1
            for m in range(i, j):
                dp[i][j] = min(dp[i][j], dp[i][m] + dp[m + 1][j] + r[i] * c[m] * c[j])

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


if __name__ == "__main__":
    main()

Python: import sys
def s():
 n=int(input())+1
 e=list(map(lambda x:x.split(),sys.stdin))
 p=[int(e[0][0])]+list(int(x[1])for x in e)
 m=[[0]*n for _ in[0]*n]
 for i in range(n):
  for r in range(n-i-1):
   c=r+i+1
   for j in range(r+1,c):
    x=m[r][j]+m[j][c]+p[r]*p[j]*p[c]
    if 1>m[r][c]or m[r][c]>x:m[r][c]=x
 print(m[r][c])
if'__main__'==__name__:s()

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

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

for l in range(1, N):
    for r in range(N-l):
        ri = R[r]
        le = C[r+l]
        DP[r][r+l] = min(ri*C[k]*le+DP[r][k]+DP[k+1][r+l] for k in range(r, r+l))
print(DP[0][N-1])

Python: n = int(input())
p = list(range(n+2))

for i in range(1,n+1):
    p[i], p[n+1] = map(int, input().split())

# table[i][j] : M_i??????M_j??????????????????????°?????????°
table = [[0] * (n+1) for i in range(n+1)]

# ??£????????£???2????????????????????????
for i in range(1,n):  # 1<=i,i+1<=n
    table[i][i+1] = p[i]*p[i+1]*p[i+2]


for k in range(3, n+1):    # ?????????k???????????????????????????3<=k<=n
    for i in range(1,n+2-k): # M_i?????????1<=i<=n-k+1
        j = i + k - 1      # M_j?????§???k??????

        table[i][j] = float('inf')

        for x in range(i, j): # M_i~M_x??¨M_(x+1)~M_j??§????????????(i<=x,x+1<=j<=n)
            # print(i, x, j)
            cost = table[i][x] + table[x+1][j] + p[i]*p[x+1]*p[j+1]
            table[i][j] = min(table[i][j], cost)
            

print(table[1][n])

Python: import itertools
n = int(input())
rc = [list(map(int, input().split())) for _ in range(n)]
rc_min = rc.index(min(rc))

def calc(rc):
    total = 0
    for i, irc in enumerate(rc):
        if i ==0:
            r, c = irc
        else:
            total += r * c * irc[1]
            c = irc[1]
    return r, c, total
def reverse_calc(rc):
    total = 0
    for i, irc in enumerate(rc[::-1]):
        if i ==0:
            r, c = irc
        else:
            total += r * c * irc[0]
            r = irc[0]
    return r, c, total

total = 0
r1, c1, ret = reverse_calc(rc[:rc_min])
total += ret
r2, c2, ret =calc(rc[rc_min:])
total += ret
total += r1 * c1 * c2
print(total)

Python: def main():
    """連鎖行列積を求める.    
    """
    n = int(input())
    inf = 10**10
    if n == 0 or n == 1:
        print(0)
        return
    if n > 1:
        p = [int(input().split()[0]) for _ in range(n-1)]
    p.extend(list(map(int, input().split())))
    m = [[inf*(i!=j) for i in range(n)] for j in range(n)]
    for l in range(1, n):
        for i in range(n-l):
            j = i+l
            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])
    print(m[0][-1])

if __name__ == "__main__":
    main()