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 <iostream>
#include <cstring>
#include <algorithm>
#include <vector>
#include <climits>


using namespace std;


using ll = long long;


const ll MAX = 100;


int main()
{
    ll n;

    cin >> n;
    vector<vector<ll>> m(n + 1);
    for (ll i = 0; i <= n; i++)
        m[i].resize(n + 1);
    vector<pair<ll, ll>> M;
    for (ll i = 0; i < n; i++) {
        ll r, c;
        cin >> r >> c;
        M.push_back(make_pair(r, c));
    }

    for (ll i = 0; i < n; i++) {
        m[i][i] += 0;
    }

    for (ll i = 0; i < n - 1; i++) {
        m[i][i + 1] += M[i].first * M[i].second * M[i + 1].second;
    }

    for (ll len = 2; len < n; len++) {
        for (ll l = 0; l < n - len; l++) {
            ll r = l + len;
            m[l][r] = LONG_LONG_MAX;
            for (ll mid = l; mid < r; mid++) {
                ll tmp = M[l].first * M[mid].second * M[r].second;
                // cout << tmp << endl;
                m[l][r] = min(m[l][r], tmp + m[l][mid] + m[mid + 1][r]);
            }
        }
    }
    cout << m[0][n - 1] << endl;
}

C++: // http://algorithms.blog55.fc2.com/blog-entry-66.html

#include <iostream>
using namespace std;
#include <stdio.h>
#include <string.h>

#define MAX 100

int SIZE;
int R[MAX + 2];
int C[MAX+1][MAX+1]; // cost table
int B[MAX+1][MAX+1]; // best table

void compute(){
	int i=0,j,k;
	memset(C,99,sizeof(C));
    
    for (i = 0; i < SIZE; i++ ) C[i][i] = 0;
    
    for (j = 1; j < SIZE; j++ ){
        for (i = 0; i < SIZE - j; i++ ){
            for (k = i; k < i + j; k++ ){
                // C[i][i+j] = min( C[i][i+j], 
                //                  C[i][k-1] + C[k][i+j] + R[i]*R[k]*R[i+j+1]);
                int cost = C[i][k] + C[k+1][i+j] + R[i]*R[k+1]*R[i+j+1];
                if ( cost < C[i][i+j] ){
                    C[i][i+j] =  cost;
                    B[i][i+j] = k;
                }
                
            }
        }
    }
}

void order( int i, int j ){
    if ( i == j ) cout << "M" << i;
    else{
        cout << "(";
        order( i, B[i][j]-1 ); order(B[i][j], j);
        cout << ")";
    }
}

void input(){
    cin >> SIZE;
	int z,i=0;
    for (; i < SIZE; i++ ) cin >> R[i]>>z;
	R[i]=z;
	//SIZE++;
}

void output(){
    cout <<  C[0][SIZE-1] << endl;
    //order(1, SIZE);
    //cout << endl;
}

main(){
    input();
    compute();
    output();
}

C++: // http://algorithms.blog55.fc2.com/blog-entry-66.html

#include <iostream>
using namespace std;
#include <stdio.h>

#define MAX 100
#define INFTY (1 << 21)

int SIZE;
int R[MAX + 2];
int C[MAX+1][MAX+1]; // cost table
int B[MAX+1][MAX+1]; // best table

void compute(){
	int i=0,j,k;
    for (; i <= SIZE; i++ )
    for (j = 0; j <= SIZE; j++ ) C[i][j] = INFTY;
    
    for (i = 0; i <= SIZE; i++ ) C[i][i] = 0;
    
    for (j = 1; j < SIZE; j++ ){
        for (i = 0; i < SIZE - j; i++ ){
            for (k = i; k < i + j; k++ ){
                // C[i][i+j] = min( C[i][i+j], 
                //                  C[i][k-1] + C[k][i+j] + R[i]*R[k]*R[i+j+1]);
                int cost = C[i][k] + C[k+1][i+j] + R[i]*R[k+1]*R[i+j+1];
                if ( cost < C[i][i+j] ){
                    C[i][i+j] =  cost;
                    B[i][i+j] = k;
                }
                
            }
        }
    }
}

void order( int i, int j ){
    if ( i == j ) cout << "M" << i;
    else{
        cout << "(";
        order( i, B[i][j]-1 ); order(B[i][j], j);
        cout << ")";
    }
}

void input(){
    cin >> SIZE;
	int z,i=0;
    for (; i < SIZE; i++ ) cin >> R[i]>>z;
	R[i]=z;
	//SIZE++;
}

void output(){
    cout <<  C[0][SIZE-1] << endl;
    //order(1, SIZE);
    //cout << endl;
}

main(){
    input();
    compute();
    output();
}

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

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 l = 2; l <= n; l++ ) {
          for ( 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>
#define NMAX 100
#define MAX 100000000
using namespace std;

struct Matrix{
  long long r;
  long long c;
};

Matrix m[NMAX];
int n;

long long minmulti_[NMAX][NMAX];

long long minmulti(int begin,int end){
  if(begin==end){return 0;}
  if(begin+1==end){return m[begin].r*m[begin].c*m[end].c;}
  if(minmulti_[begin][end]!=0) return minmulti_[begin][end];
  long long min=MAX;
  long long num;
  for(int i=begin;i<end;i++){
     num = minmulti(begin,i) + minmulti(i+1,end);
     num += m[begin].r*m[i].c*m[end].c;
     if(num<min){min=num;}
  }
  minmulti_[begin][end]=min;
  return min;
}

int main(){
  for(int i=0;i<NMAX;i++){
    for(int j=0;j<NMAX;j++){
      minmulti_[i][j]=0;
    }
  }
  cin>>n;
  for(int i=0;i<n;i++){
    cin>>m[i].r>>m[i].c;
  }
  cout<<minmulti(0,n-1)<<endl;
}

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

int main()
{
    int n;
    cin >> n;
    long long p[n + 1];
    for (int i = 0; i < n; i++)
    {
        cin >> p[i] >> p[i + 1];
    }
    long long m[n + 1][n + 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++)
        {
            int j = i + l - 1;
            m[i][j] = 1 << 21;
            for (int k = i; k <= j; 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;
}