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<iostream>
#include<stdio.h>
#include<stdlib.h>

using namespace std;



int main(){
  int n;
  cin>>n;
  int r[100];
  int m[101][101];
  int j;
  int q=0;
  //int c[n];
  for(int i=1;i<=n;i++){
    cin>>r[i]>>r[i-1];
  }
  for(int i=1;i<=n;i++){
    m[i][i]=0;
  }
  for(int l=2;l<=n;l++){
    for(int i=1;i<=n-l+1;i++){
      j=i+l-1;
      m[i][j]=(1<<21);
      for(int k=i;k<j;k++){
	q=m[i][k]+m[k+1][j]+r[i-1]*r[k]*r[j];
	m[i][j]=min(m[i][j],q);
      }
    }
  }
  
  cout<<m[1][n]<<endl;
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0; i<n; i++)
typedef long long ll;
typedef long long unsigned int llu;
ll MOD = 1000000007;
ll INF = 1000000009;

int a[110];
int b[110];
int dp[110][110];
/*
dp[i][j]:行列i~jまでの乗算回数の最小値
dp[i][j]=min(dp[i-1][j]+(a[i-1]*b[i-1]*[b[j]])), dp[i][j+1]+(a[i]*a[j+1]*b[j+1]))
*/

void solve(){

    int n;
    cin >> n;
    rep(i,n){
      cin >> a[i] >> b[i];
    }
    rep(i,110){
      rep(j,110){
          dp[i][j]=0;
      }
    }
    
    for(int i=1; i<n; i++){
        dp[i-1][i]=a[i-1]*b[i-1]*b[i];
    }
    

    for(int i=2; i<n; i++){
        for(int j=0; j<n-i; j++){
            int ans = INF;
            int x = j;
            int y = i+j;
            for(int k=0; k<y-x; k++){
                ans = min(int(ans), int(dp[x][x+k]+dp[x+k+1][y]+a[x]*b[x+k]*b[y]));
            }
            dp[j][i+j]=ans;
        }
    }

    /*
    rep(i,n){
        rep(j,n){
            cout << dp[i][j] << " ";
        }
        cout << endl;
    }
    */

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

}


int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  solve();
  return 0;
}

C++: //
//  main.cpp
//  longest_common_subsequence
//
//  Created by ???????????? on 2017/10/17.
//  Copyright ?? 2017 ????????????. All rights reserved.
//

#include <iostream>
#include <stdio.h>
#include <string.h>

using namespace std;

char X[1005];
char Y[1005];

void lcs(){
    size_t m = strlen(X);
    size_t n = strlen(Y);
    int c[m+1][n+1];
    c[0][0] = 0;
    for (int i = 1; i <= m; i++) c[i][0] = 0;
    for (int j = 1; j <= n; j++) c[0][j] = 0;
    for (int i = 1; i <= m; i++){
        for(int j = 1; j <= n; j++){
            if (X[i] == Y[j]){
                c[i][j] = c[i-1][j-1]+1;
            }
            else if(c[i-1][j] >= c[i][j-1]){
                c[i][j] = c[i-1][j];
            }
            else{
                c[i][j] = c[i][j-1];
            }
        }
    }
    cout << c[m][n] << endl;
//    cout << c[m+1][n+1] << endl;
}

int main(int argc, const char * argv[]) {
    int n, i;
    scanf("%d", &n);
    for (i = 0; i < n; i++){
        scanf("%s", X);
        scanf("%s", Y);
        lcs();
    }
//    std::cout << "Hello, World!\n";
    return 0;
}

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

int main() {

  int n;
  cin >> n;

  // l × m 行列と m × n 行列の積では、l × m × n 回の計算が生じる
  // M_i を p_i-1 × p_i 行列とすると、M_i × M_i+1 の計算回数は、p_i-1 × p_i × p_i+1 となる
  // M_1, M_2, M_3 が与えられたとき、((M_1 × M_2) × M_3) と (M_1 × (M_2 × M_3)) の計算量が少ない方を選択する

  // p:M_i を p_i-1 × p_i 行列とする
  vector<int> p(n+1);
  for (int i = 1; i <= n; i++) {
    cin >> p[i-1] >> p[i];
  }

  // cost[i][j]:M_i から M_j までの最小計算量
  vector<vector<int>> cost(n+1, vector<int> (n+1));

  // i から l 個まで調べる
  for (int l = 2; l <= n; l++) {
    for (int i = 1; i <= n - l + 1; i++) {
      // i から l までの個数
      int j = i + l - 1;
      // 大きい数値を入れておく
      cost[i][j] = 1000000007;
      // i から j 回調べる
      for (int k = i; k < j; k++){
        cost[i][j] = min(cost[i][j], cost[i][k] + cost[k+1][j] + p[i - 1] * p[k] * p[j]);
      }
    }
  }

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

  return 0;

}

C++: #include<iomanip>
#include<limits>
#include<thread>
#include<utility>
#include<iostream>
#include<string>
#include<algorithm>
#include<set>
#include<map>
#include<vector>
#include<stack>
#include<queue>
#include<cmath>
#include<numeric>
#include<cassert>
#include<random>
#include<chrono>
#include<unordered_map>
#include<fstream>
#include<list>
#include<typeinfo>
#include<functional>
#include<complex>
using namespace std;
typedef unsigned long long int ull;
typedef long long int ll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pi;
typedef pair<double,double> pd;
typedef pair<double,ll> pdl;
#define F first
#define S second
const ll E=1e18+7;
const ll MOD=1000000007;



int main(){
    ll n;
    cin>>n;
    vector<vector<ll>> dp(n+1,vector<ll>(n+1,E));
    vector<pll> A(n);
    for(int i=0;i<n;i++){
        dp[1][i]=0;
        ll r,c;
        cin>>r>>c;
        A[i]={r,c};
    }
    for(int i=2;i<=n;i++){
        for(int t=0;i+t<=n;t++){
            for(int h=0;h+1<i;h++){
                //cout<<i<<" "<<t<<" "<<h<<endl;
                dp[i][t]=min(dp[i][t],dp[h+1][t]+dp[i-h-1][t+h+1]+A[t].F*A[t+h].S*A[t+i-1].S);
            }
        }
    }
    cout<<dp[n][0]<<endl;
    
    
    return 0;
}