Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

func nextStr() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list {
		buf.Write([]byte(fmt.Sprintf(" %d", v)))
	}
	buf.Write([]byte("\n"))
	buf.Flush()
}

//solve
//単純な場合
func matrixChainMultiplication() {
	//行列が1つだけのとき
	for i := 1; i <= n; i++ {
		m[i][i] = 0
	}
	for l := 2; l <= n; l++ {
		for i := 1; i <= n-l+1; i++ {
			j := i + l - 1
			m[i][j] = 1 << 21
			//kまでで区切る
			for 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])
			}
		}
	}
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

func min(a, b int) int {
	if a > b {
		return b
	} else {
		return a
	}
}

const MAX = 100

var n int
var p [MAX + 1]int

//m[i][j]: Mi * Mi+1 * ... * Mjを計算するときに必要なスカラー乗算の最小回数
var m [MAX + 1][MAX + 1]int

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 1; i <= n; i++ {

		p[i-1] = nextInt() //行数
		p[i] = nextInt()   //列数
	}

	matrixChainMultiplication()
	fmt.Println(m[1][n])
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
  int n,p[105],m[105][105];
  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 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]);
      }
    }
  }
  cout << m[1][n] << endl;
}

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

static const int N = 100;

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

C++: #include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#include <stack>
#include <queue>
#include <list>
#include <map>
#include <set>
#include <string>
#include <cstring>
#include <sstream>
#include <cmath>
#include <functional>
#include <fstream>
#include <cstdlib>
typedef long long ll;
const int MOD = 1e9+7;


#define REP(i, N) for (int i = 0; i < (N); i++)
#define REPP(i, a, b) for (int i = (a); i < (b); i++)
#define ALL(v) (v).begin(), (v).end()
#define RALL(v) (v).rbegin(), (v).rend()
#define VSORT(c) sort((c).begin(),(c).end())
#define SZ(x) ((int)(x).size())
//vvintを作る　マクロで　 #define vvint(N,M) vector<vector<int>>

using namespace std;

int main(){
    
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    vector<int> p(101);
    ll dp[101][101];
    REPP(i,1,n+1) cin >> p[i-1] >> p[i];
    REPP(i,1,n+1) dp[i][i]=0;

    for(int i = 2; i <= n;i++){
        for(int l = 1; l <= n - i + 1;l++){
            int j =  i  +  l - 1;
            dp[l][j] = (1 << 21);
            for(int k = l; k <= j - 1;k++){
            dp[l][j] = min(dp[l][j],dp[l][k] + dp[k+1][j] + p[l-1]*p[k]*p[j]);
            }
        }
    }
    cout << dp[1][n] << endl;
    return 0;
}

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 h=2;h<=n;h++){
        for(int i=1;i<=n-h+1;i++){
            int j=i+h-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]);
            }
        }
    }
    cout<<m[1][n]<<endl;
    return 0;
}