Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)
	mm := make([]int, n+1)
	dp := make([][]int, n+1)
	for i := 0; i <= n; i++ {
		dp[i] = make([]int, n+1)
	}
	for i := 0; i < n; i++ {
		mm[i] = getNextInt(scanner)
		mm[i+1] = getNextInt(scanner)
	}

	for l := 2; l <= n; l++ {
		for i := 1; i <= n-l+1; i++ {
			j := i + l - 1
			for k := i; k <= j-1; k++ {
				d := dp[i][k] + dp[k+1][j] + mm[i-1]*mm[k]*mm[j]
				if dp[i][j] == 0 || dp[i][j] > d {
					dp[i][j] = d
				}
			}
		}
	}

	fmt.Fprintln(writer, dp[1][n])

	writer.Flush()
}

C++: #include<bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i) 
#define PI acos(-1)

using namespace std;
using ll = long long;
using P = pair<int, int>;
using LP = pair<ll, ll>;

template<class T> inline bool chmax(T& a, T b) {if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) {if (a > b) { a = b; return true; } return false; }

ll dpRec(int l, int r, vector<vector<ll>>& dp, vector<LP> rc) {
    if (dp[l][r] != INT_MAX) return dp[l][r];
    if (r - l == 1) {
        dp[l][r] = 0;
        return 0;
    }
    for (int i = l + 1; i < r; ++i) {
        chmin(dp[l][r], dpRec(l, i, dp, rc) + dpRec(i, r, dp, rc) + rc[l].first * rc[i].first * rc[r - 1].second);
    }
    return dp[l][r];
}

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

    int n;
    cin>>n;
    vector<LP> rc(n);
    rep(i, n) cin>>rc[i].first>>rc[i].second;

    vector<vector<ll>> dp(n + 1, vector<ll>(n + 1, INT_MAX));
    // for (int i = 2; i < n + 1; ++i) {           // 行列をi個選ぶ
    //     for (int j = 0; j < n - i + 1; ++j) {   // j番目の行列以降から
    //         for (int k = 1; k < i; ++k) {       // j番目からk個までとそれ以降の積
    //             chmin(dp[i][j], dp[k][j] + dp[i - k][j + k] + rc[j].first * rc[j + k].first * rc[j + i].first);
    //         }
    //     }
    // }
    cout<<dpRec(0, n, dp, rc)<<endl;
}

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

static const int N = 100;

int main(){
  int n,p[N+1],m[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++) m[i][i]=0;

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

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

  return 0;
}

C++: #include <vector>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <algorithm>
#include <numeric>
#include <utility>
#include <sstream>
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <string>
#include <cstring>
#include <complex>
#include <ctime>
#include <cstdlib>

using namespace std;

inline int to_int(string s) {int v; istringstream sin(s); sin >> v; return v;}
template<class T> inline string to_str(T x) {ostringstream sout; sout << x; return sout.str();}

typedef long long ll;
typedef pair<int, int> P;
const int INF = 1<<22;

// dp[i][j] := [i , j]??????????????????????????則???????????????????属???即????????属
// |(4*5   (5*3)  3*2)|  2*1
int main()
{
	int n, dp[128][128], r[128];
	P T[128];

	cin >> n;

	for(int i = 0; i < n; i++)
	{
		for(int j = 0; j < n; j++)
		{
		 	dp[i][j] = INF;
		}
	}
	/*
	for(int i = 0; i < n; i++)
	{
		dp[i][i] = 0;
	}
	*/
	for(int i = 0; i < n; i++)
	{
		cin >> T[i].first >> T[i].second;
		dp[i][i] = 0;
	}
	/*
	r[0] = T[0].first;
	for(int i = 0; i < n; i++)
	{
		r[i+1] = T[i].second;
	}
	*/
	/*
	for(int i = 0; i <= n; i++)
	{
		cout << r[i] << endl
	}
	*/
	/*
	for(int l = 1; l < n; l++)
	{
		for(int i = 0; i < n-l; i++)
		{ 
			int j = i + l;
			for(int k = 1; k <= l; k++)
			{
				dp[i][j] = std::min(dp[i][j], dp[i][i + k - 1] + dp[i + k][j] + T[i].first*T[i + k].first*T[j].second); //r[j]*r[k]*r[i+j+1]);
			}
		}
	}
*/
	for(int i = 1; i < n; i++)
	{
		for(int j = 0; j < n-i; j++)
		{ 
			for(int k = 1; k <= i; k++)
			{
				dp[i][j] = std::min(dp[i][j], dp[k-1][j] + dp[i-k][j+k] + T[j].first*T[j + k].first*T[j + i].second); //r[j]*r[k]*r[i+j+1]);
				printf("%3d : %3d : %3d => %3d\n", i, j, k, dp[i][j]);
				//puts("run");
			}
		}
	}

	/*
	for(int i = 0; i < n; i++)
	{
		for(int j = 0; j < n; j++)
		{
			printf("%10d ",dp[i][j]);
		}
		puts("");
	}
	*/

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

C++: #include <iostream>
#include <algorithm>
#include <cstdio>
const int N = 101;

int n;
long m[N][N], p[N+2];
int j;

int matrixChainOrder(){
  for(int i=0; i<n; i++){ m[i][i] = 0; }
  for(int l=2; l<=n; l++){
    for(int i=1; i+l-1<=n; i++){
      j = i+l-1;
      m[i][j] = 100000000;
      for(int k=i; k<j-1; k++){
        m[i][j] = std::min(m[i][j], m[i][k] + m[k+1][j] + p[i-1]*p[k]*p[j]);
      }
    }
  }
  return m[1][n];
}

int main(){
  std::cin >> n; //number of matrix

  for(int i=1; i<=n; i++){
    std::cin >> p[i-1] >> p[i];
  }
  std::cout << matrixChainOrder() << std::endl;
  return 0;
}

C++: #include <cassert>
#include <climits>
#include <iostream>
#include <vector>

class Matrix {
  public:
    long long x;
    long long y;
    long long cost;
};

int main()
{
  int n;
  std::cin >> n;
  std::vector<Matrix> matrix(n);
  for (int i = 0; i < (int)matrix.size(); i++) {
    std::cin >> matrix.at(i).x >> matrix.at(i).y;
  }
  std::vector<std::vector<Matrix>> memo(n+1, std::vector<Matrix>(n));
  for (int i = 0; i < (int)matrix.size(); i++) {
    memo.at(1).at(i).x = matrix.at(i).x;
    memo.at(1).at(i).y = matrix.at(i).y;
  }
  for (int block = 2; block <= (int)matrix.size(); block++) {
    for (int i = 0; i + block <= (int)matrix.size(); i++) {
      long long result = LLONG_MAX;
      memo.at(block).at(i).x = matrix.at(i).x;
      memo.at(block).at(i).y = matrix.at(i+block-1).y;
      for (int part = i+1; part < i + block; part++) {
        long long tmp = 0;
        assert(memo.at(part-i).at(i).y == memo.at(block-part+i).at(part).x);
        tmp += memo.at(part-i).at(i).cost + memo.at(block-part+i).at(part).cost;
        tmp += memo.at(part-i).at(i).x * memo.at(part-i).at(i).y * memo.at(block-part+i).at(part).y;
        result = std::min(result, tmp);
      }
      memo.at(block).at(i).cost = result;
    }
  }
  if (matrix.size() == 1) {
    std::cout << "0" << std::endl;
  } else {
    std::cout << memo.at(matrix.size()).at(0).cost << std::endl;
  }
  return 0;
}

C++: #include <bits/stdc++.h>
#include <tuple>

#define REP(i, n) for(int i=0;i<(int)(n);i++)
#define ALL(x) (x).begin(),(x).end()
const int INF = 1e9;

using namespace std;
int dp[100][100];
int size[100][2];

int main() {
    int n;
    cin >> n;
    REP(i, 100) REP(j, 100)
        dp[i][j] = INF;
    REP(i, n)
        cin >> size[i][0] >> size[i][1];
    REP(i, n) for(int j = 0; j < n - i; j++){
        if(i == 0){
            dp[i][j] = 0;
            continue;
        }
        if(i == 1){
            dp[i][j] = size[j][0] * size[j][1] * size[j+1][1];
            continue;
        }
        REP(k, i){
            dp[i][j] = min(dp[i][j], dp[k][j] + dp[i-1-k][j+k+1] + size[j][0] * size[j+k][1] * size[j+i][1]);
        }
    }
    cout << dp[n-1][0] << endl;
    return 0;
}