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<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll,ll> pll;

vector<ll> r(101);
vector<ll> c(101);
vector<vector<ll>> DP(101,vector<ll> (101,-1));

ll inf=1e18;



ll dp(ll l,ll h) {
  if(DP[l][h]>-1) {
    return DP[l][h];
  }
  ll res=inf;
  if(l+1==h) {
    res=0;
  }
  else {
    for(ll i=l+1;i<h;i++) {
      res=min(res,dp(l,i)+dp(i,h)+r[i]*r[l]*c[h-1]);
    }
  }
  return DP[l][h]=res;
}

int main() {
  ll n;
  cin >> n;
  for(ll i=0;i<n;i++) {
    cin >> r[i] >> c[i];
  }
  cout << dp(0,n) << endl;
}

C++: #include <iostream>
#include <algorithm>
#include <cstdint>

using namespace std;

static const int N = 100;
static int m[N + 1][N + 1] = {}, p[N + 1] = {};

static inline void matrixChainMultiplication(int n) {
  for (int l = 2; l <= n; l++) {
    for (int i = 1; i <= n - l + 1; i++) {
      int j = i + l - 1;
      m[i][j] = INT_MAX;
      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]); 
      }
    }
  }
}

int main() {
  int n;
  cin >> n;
  
  for (int i = 1; i <= n; i++) {
    cin >> p[i - 1] >> p[i];
  }

  matrixChainMultiplication(n);
  
  cout << m[1][n] << endl;

  return 0;
}

C++: #include<iostream>
using namespace std;
int min(int a,int b){return a<b?a:b;}
int p[101],m[101][101];
int main()
{	int n;
	cin>>n;
	for(int i=1;i<=n;i++)//总共有n+1个有效数据
		cin>>p[i-1]>>p[i];//保证只有n个有效的数据重复的不管
	for(int i=1;i<=n;i++)
		m[i][i]=0;
	for(int l=2;l<=n;l++)//这个l状态积累量
	{
		for(int i=1;i<=n-l+1;i++)
		{	int j=i+l-1;
			m[i][j]=(1<<21);//极大取极小,这个地方要有括号
			for(int k=i;k<=j-1;k++)//从i开始,对l开始累加
			{
				m[i][j]=min(m[i][j],m[i][k]+m[k+1][j]+p[i-1]*p[k]*p[j]);
			}

		}
	}
	cout<<m[1][n]<<endl;
	return 0;
}

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

static const int N=100;

//求解矩阵链乘法的最优解
//p 用于存储矩阵的行和列的
//dp[i][j] 表示从矩阵i乘到矩阵j的最小乘法次数

int main(){
    int n;
    int p[N+1],dp[N+1][N+1];

    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>p[i-1]>>p[i];
    }

    for(int i=1;i<n;i++){
        dp[i][i]=0;
    }
    for(int l=2;l<=n;l++){
        for(int i=1;i<=n-l+1;i++){
            int j=i+l-1;
            dp[i][j]=(1<<21);//取一个很大的值
            for(int 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]);
            }
        }
    }

    cout<<dp[1][n]<<endl;

    return 0;
}

C++: #include <stdio.h>

#define MAX_N 100
#define INF 1e8

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

C++: #include <iostream>
using namespace std;

int n, p = 0, min = 101, mini;
int v[101];

int main()
{
	cin >> n;

	for (int i = 0; i < n; i++) {
		cin >> v[i] >> v[i + 1];
		if (min > v[i]) {
			min = v[i];
			mini = i;
		}
	}

	for (int j = 0; j < n; j++)
		p += v[j] * v[j + 1];
	p += v[0] * v[n];

	if (mini == 0)
		p -= v[0] * v[1];
	else if (mini == n)
		p -= v[n - 1] * v[n];
	else
		p -= v[mini] * (v[mini + 1] + v[mini - 1]);

	p *= v[mini];

	cout << p << endl;

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)   FOR(i,0,n)
#define ALL(a)     (a).begin(),(a).end()
#define VI         vector<int>
#define MOD 1000000007

using ll = long long int;
using P = pair<int,int>;

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

//const ll INF=(ll)1e19;
const int INF=(1<<30);

vector<int> r;
vector<int> c;
int dp[105][105];


int main(){
  int n;
  cin >> n;
  REP(i,n){
    int rr,cc;
    cin >> rr >> cc;
    r.emplace_back(rr);
    c.emplace_back(cc);
  }

  REP(i,n)REP(j,n)dp[i][j]=INF;

  REP(i,n)REP(j,n){
    if(j+i >=n)continue;
    if(i==0){
      dp[j][j] = 0;
    }else{

      FOR(k,j,j+i){
        chmin(dp[j][j+i], dp[j][k] + r[j]*c[k]*c[j+i] + dp[k+1][j+i]);
      }
    }
  }

  cout << dp[0][n-1] << endl;
}