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++: #define _CRT_SECURE_NO_WARNINGS
#include <cstdio>
#include <cstdlib>
#include <string>
#include <iostream>
#include <climits>

using namespace std;

int main() {
	int i, j, k, to, min, temp_result;
	int n;
	int r[100], c[100];
	int result[100][100];
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> r[i] >> c[i];
		result[i][i] = 0;
	}
	
	i = 0;
	j = 1;
	to = n - 2;
	while (j <= n - 1) {
		while (i <= to) {
			//computation of result[i][i+j]
			min = INT_MAX;
			k = i;
			while (k <= i + j - 1) {
				temp_result = c[k] * r[i] * c[i + j] + result[i][k] + result[k + 1][i + j];
				if (temp_result < min) {
					min = temp_result;
				}
				k++;
			}
			result[i][i + j] = min;
			i++;
		}
		i = 0;
		j++;
		to--;
	}
	printf("%d", result[0][n - 1]);
}

C++: #include<iostream>
#include<cstdio>
#define INT_MAX 100000000
using namespace std;
int index;
int mm[1000][1000];
int mine = INT_MAX;

void solve(int p[]){
  int n = index-1,j,q;
  for(int i=1;i<=n;i++)mm[i][i]=0;
  for(int l=2;l<=n;l++){
    for(int i=1;i<=n-l+1;i++){
      j = i+l-1;
      mm[i][j] = INT_MAX;
      for(int k=i;k<=j-1;k++){
	q = mm[i][k] + mm[k+1][j] + p[i-1]*p[k]*p[j];
	if(q<mm[i][j]){
	  mm[i][j] = q;
       
	}

      }
    }
  }




}

int main(){
  int p[1000],a,b;
  scanf("%d",&index);
  //for(int i=0;i<=index;i++)for(int j=0;j<=n;j++)mm[i][j] = INT_MAX;
  for(int i=0;i<index;i++){
    scanf("%d %d",&a,&b);
    p[i] = a;
    if(i == index-1)p[i+1] = b;
  }

  index = index+1;
  solve(p);
 
  printf("%d\n",mm[1][index-1]);
  return 0;
}

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

int n;

int main(void) {

    cin >> n;
    int m[n + 1][n + 1] = {};
    int p[n + 1] = {}; // p[i - 1] x p[i]の行列を表す

    for (int i = 0; i < n; ++i) {
        cin >> p[i] >> p[i + 1];
    }

    // 範囲が1の場合は計算しないので0
    for (int i = 1; i <= n; ++i) {
        m[i][i] = 0;
    }

    // l    : 対象とする行列の個数
    // i    : スタート地点
    // j    : ゴール地点
    // k    : 括弧を切るポイント
    for (int l = 2; l <= n; ++l) {
        for (int i = 1; i <= n - l + 1; ++i) {
            int j = i + l - 1;
            m[i][j] = INT32_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]);
            }
        }
    }

    // for (int i = 1; i <= n; ++i) {
    //     for (int j = i + 1; j <= n; ++j) {
    //         m[i][j] = INT32_MAX;
    //         for (int k = i; k < j; ++k) {
    //             // i ~ k, (k + 1) ~ jの行列計算
    //             // それまでの計算回数 + 新しい計算回数
    //             // それまでの計算回数はm[i][k] + m[k + 1][n]
    //             // 新しい計算回数は左の行 * 中間の列 * 右の列
    //             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 <algorithm>
#include <iostream>
#include <vector>

#define INF 1000000007

int main(){
    int n;
    std::cin >> n;

    std::vector<int> row(n), col(n);
    for(int i = 0; i < n; ++i){
        std::cin >> row.at(i) >> col.at(i);
    }

    // consider a n * n dp matrix with INF as the minimum value is the interest of this exercise
    std::vector<std::vector<int>> dp(n, std::vector<int>(n, INF));
    for(int l = n - 1; 0 <= l; --l){
        for(int r = 0; r < n; ++r){
            if(r == l){
                // set the dp value at self multiplication zero
                dp.at(l).at(r) = 0;
            }else if(r == l + 1){
                // multiply 2 matrixes
                dp.at(l).at(r) = row.at(l) * col.at(l) * col.at(r);
            }else if(r > l + 1){
                for(int m = l; m < r; ++m){
                    // examine the all dp values in every case where a separating point differs each other
                    dp.at(l).at(r) = std::min(dp.at(l).at(r), dp.at(l).at(m) + row.at(l) * col.at(m) * col.at(r)+ dp.at(m + 1).at(r));
                }
            }
        }
    }

    std::cout << dp.at(0).at(n - 1) << std::endl;

    return 0;
}

C++: #include<bits/stdc++.h>
#define INF 1e9

using namespace std;

int main()
{
  int n;
  int a[105];
  
  cin >> n;

  for(int i=0;i < n;i++){
    cin >> a[i] >> a[i+1];
  }
  //dp[i][j] := iからj番目の行列積に必要なスカラー積の最小値
  int dp[105][105] = {};

  //init
  for(int i=0;i < n;i++){
    for(int j=0;j < n;j++){
      if(i == j) dp[i][j] = 0;//iからiまでは当然 0回
      else dp[i][j] = INF;
    }
  }
  
  for(int m = 0; m < n ;m++){
    for(int i = 0; i+m < n ;i++){
      int j = i+m;
      for(int k = i; k < j ;k++){
	dp[i][j] = min(dp[i][j], dp[i][k] + dp[k+1][j] + a[i]*a[k+1]*a[j+1]);
      }
    }
  }
  cout << dp[0][n-1] << endl;
  return 0;
}