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
}

C++: #include <cstdio>
#include <algorithm>
using namespace std;

int MatrixChainMaltiplication(int *p, int n) {
    int m[n+1][n+1];
    for (int i=0; i<=n; i++) m[i][i] = 0;

    for (int l=2; l<=n; l++) {
        for (int i=1; i<=(n-l+1); i++) {
            int j = i + l - 1;
            m[i][j] = (1 << 21);
            for (int k=i; k<=j-1; k++) {
                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];
}

int
main()
{
    int n;
    scanf("%d", &n);
    int p[n+1];
    for (int i=0; i<n; i++) {
        int a, b;
        scanf("%d %d", &a, &b);
        if (i == 0) p[i] = a;
        p[i+1] = b;
    }
    printf("%d\n", MatrixChainMaltiplication(p, n));
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long llong;
#define MAX 100
#define INFTY 9999999

// 行列群を保持しておく
vector<int> vecMtr(MAX);
vector<vector<int>> dp(MAX,vector<int>(MAX));

int
MultipleMatrixChain(int size)
{
  for (int i = 1; i < size; i++)
  {
    dp[i][i] = 0;
  }
  
  for (int l = 2; l <= size; l++)
  {
    for (int i = 1; i <= size-l+1; i++)
    {
      int j = i + l - 1;
      dp[i][j] = INFTY;
      for (int k = i; k <= j-1; k++)
      {
        dp[i][j] = min(dp[i][j], dp[i][k] + dp[k+1][j]+ vecMtr[i-1]*vecMtr[k]*vecMtr[j]);
      }
    }
  }
  return dp[1][size];
}

int main() {
  int n;
  cin >> n;
  
  int r = 0;
  int c = 0;

  for (int i = 1; i <= n; i++)
  {
      cin >> r >> c;
      vecMtr[i-1] = r;
      vecMtr[i] = c;
  }
  
  cout << MultipleMatrixChain(n) << "\n";
}

C++: #include <stdio.h>
#include <algorithm>
using namespace std;
int n, r[100], c[100], dp[100][101];
int main() {
	scanf("%d", &n);
	for(int i = 0; i < n; i++) scanf("%d%d", &r[i], &c[i]), dp[i][i] = 0;
	for(int i = 1; i < n; i++) {
		for(int j = 0; i + j <= n; j++) {
			dp[j][i + j] = min(dp[j][i + j - 1], dp[j + 1][i + j]) + r[j] * c[i + j - 1];
		}
	}
	printf("%d\n", dp[0][n]);
	return 0;
}

C++: //#include <bits/stdc++.h>
#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <cmath>
#include <algorithm>
#include <map>
#include <iomanip>
#include <stdlib.h>
#include <stdio.h>
#include <queue>
#include <deque>
#include <set>
#include <stack>
#include <time.h>
 
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef pair<int, int> Pii;
typedef pair<int, ll> Pil;
typedef pair<ll, ll> Pll;
typedef pair<ll, int> Pli;

#define fi first
#define se second
#define mp make_pair
 
const ll MOD = 1e9 + 7;
const ll MOD2 = 998244353;
const ll INF = 1ll << 60;
const double PI = 2 * asin(1);

void yes() {printf("yes\n");}
void no() {printf("no\n");}
void Yes() {printf("Yes\n");}
void No() {printf("No\n");}
void YES() {printf("YES\n");}
void NO() {printf("NO\n");}

int N;
ll r[105], c[105], DP[105][105];

ll Calc(int L, int R){
  if (DP[L][R] != 0) return DP[L][R];
  if (L == R) return DP[L][R] = 0;

  ll ans = INF;
  for (int k = L; k < R; k++){
    ll now = r[L] * c[k] * c[R];
    now += Calc(L, k) + Calc(k + 1, R);
    ans = min(now, ans);
  }
  
  return DP[L][R] = ans;
}

int main(){
  cin >> N;
  for (int i = 0; i < N; i++) cin >> r[i] >> c[i]; 
  cout << Calc(0, N - 1) << endl;
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
const long long INF = 1000000000;
long long matrix_chain_multiplication(vector<long long> &A){
    int n = A.size() - 1;
    vector<vector<long long>> dp(n, vector<long long>(n, INF));
    for (int i = 0; i < n; i++){
        dp[i][i] = 0;
    }
    for (int i = 1; i < n; i++){
        for (int j = 0; j < n - i; j++){
            for (int k = j; k < j + i; k++){
                dp[j][j + i] = min(dp[j][j + i], dp[j][k] + dp[k + 1][j + i] + A[j] * A[k + 1] * A[j + i + 1]);
            }
        }
    }
    return dp[0][n - 1];
}
int main(){
  int n;
  cin >> n;
  vector<long long> H(n + 1);
  for (int i = 0; i < n; i++){
    cin >> H[i] >> H[i + 1];
  }
  cout << matrix_chain_multiplication(H) << endl;
}

C++: #include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<climits>
#include<iostream>
#include<sstream>
#include<utility>
#include<map>
#include<vector>
#include<queue>
#include<algorithm>
#include<set>
#include<stack>
using namespace std;
typedef long long ll;
typedef pair<int,int>P;
int N;
int r[105],c[105];
ll dp[105][105]={0};

void dbg()
{
	for(int i=0;i<N;i++,puts(""))
		for(int j=0;j<N;j++)
			printf("%7d ",dp[i][j]);
}

int main()
{
	scanf("%d",&N);
	for(int i=0;i<N;i++)
		scanf("%d%d",&r[i],&c[i]);
	for(int i=0;i<N;i++)dp[i][i]=0;
	for(int l=1;l<N;l++)
		for(int i=0;i<N-l;i++)
		{
			int j=i+l;
			dp[i][j]=10000000;
			for(int k=0;k<j;k++)
				dp[i][j]=min(dp[i][j],dp[i][k]+dp[k+1][j]+r[i]*c[k]*c[j]);
		}
	printf("%d\n",dp[0][N-1]);
	return 0;
}