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 <cstdlib>
#include <climits>

/*
 * http://ttrsq.exblog.jp/24318687/
 */

const int MAX_N = 100;
int DP[MAX_N + 1][MAX_N + 1] = {0};
int *p;

int best(int r, int c) {
  int min = INT_MAX;
  int num = c - r;

  for (int i = 0; i < num; i++) {
    min = std::min(min, DP[r][r + i] + DP[r + i + 1][c] + p[r - 1] * p[r + i] * p[c]);
  }
  
  return min;
}

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

  int n = 0;
  std::cin >> n;

  if (n == 1) {
    std::cout << "1" << std::endl;
  }
  
  p = (int *) std::malloc(sizeof(int) * n + 1);

  int bb = 0;

  std::cin >> p[0];
  std::cin >> p[1];
  
  for (int i = 2; i <= n; i++) {
    std::cin >> bb;
    std::cin >> p[i];
  }

  for (int i = 1; i < n; i++) {
    DP[i][i + 1] = p[i - 1] * p[i] * p[i + 1];
  }

  for (int j = 0; j <= n - 3; j++) {
    for (int i = j + 3; i <= n; i++) {
      DP[i - 2 - j][i] = best(i - 2 - j, i);
    }
  }

  std::cout << DP[1][n] << std::endl;

  return 0;
}

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

static const in N = 100;

int main(){
  int j,i,l,n,p[N+1],m[N+1][N+1];
  scanf("%d",&n);

  for(i = 0;i<=n;i++){
    scanf("%d %d",&p[i-1],&p[i]);
  }

  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);
      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<bits/stdc++.h>
using namespace std;
#define int long long
int n,dp[111][111],p[111];

int rec(int i,int j){
  int Min=2*1e9;
  for(int k=0;k<i-1;k++){
    Min=min(Min,dp[j+1][j+k+1]+dp[j+k+2][j+i]+p[j]*p[j+k+1]*p[j+i]);
  }
  return Min;
}

signed main(){
  cin>>n;
  cin>>p[0]>>p[1];
  for(int i=2;i<=n;i++){
    cin>>p[i]>>p[i];
  }
  for(int i=0;i<n;i++){
    dp[i][i]=0;
    if(i)dp[i][i+1]=p[i-1]*p[i]*p[i+1];
  }

  for(int i=3;i<=n;i++){
    for(int j=0;j+i<=n;j++){
      dp[j+1][j+i]=rec(i,j);
    }
  }
  cout<<dp[1][n]<<endl;
  return 0;
}

C++: #include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<iostream>
using namespace std;

#define N_MAX 100
#define C_MAX 100
#define R_MAX 100

int p[N_MAX+1];
int m[R_MAX+1][C_MAX+1];


int chain_multiplication(int n)
{
    for (int i = 0; i < n; i++) {
        m[i][i] = 0;
    }
    for (int l = 1; l < n; l++) {
        for (int i = 0; i < n - l; i++) {
            int j = i + l;
            m[i][j] = 100000000;
            for ( int k = i ; k < j; k++) {
                int a = m[i][k] + m[k+1][j] + p[i] * p[k+1] * p[j+1];
//                printf("i %d k %d j %d a %d min %d\n", i, k, j, a, m[i][j]);
                if (m[i][j] > a) {
                    m[i][j] = a;
                }
            }
//            printf("m[%d][%d] = %d\n", i, j, m[i][j]);
        }
    }
    return m[0][n-1];
}

int main() {
    int n;

    cin >> n;

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

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(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<bits/stdc++.h>
#define rep(i, n) for (int i=0; i<(n); i++)
#define ll long long
using namespace std;

const ll INF=1e18;

int main() {
  int n; cin>>n;
  vector<ll> p(n+1);
  rep(i, n) cin>>p[i]>>p[i+1];

  vector<vector<ll>> dp(n+1, vector<ll>(n+1, INF));
  rep(i, n+1) dp[i][i]=0;

  for (int l=1; l<n; l++) {
    for (int i=0; i<n-l; i++) {
      int j=i+l;
      for (int k=i; k<j; k++) {
        ll cost=p[i]*p[k+1]*p[j+1];
        dp[i][j]=min(dp[i][j], dp[i][k]+dp[k+1][j]+cost);
      }
    }
  }
  cout<<dp[0][n-1]<<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 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<algorithm>
using namespace std;

int matrixChainMultiplication(int **m,int *p,int n);

const int Sentinel = 2000000;

int main(){
	int n,row,column,*p,**m; cin>>n;
	p = new int[n+1];
	for(int i=1;i<=n;i++){
		cin>>row>>column;
		p[i-1] = row; p[i] = column;
	}

	m = new int*[n+1]; for(int i=0;i<=n;i++) m[i] = new int[n+1];

	cout<<matrixChainMultiplication(m,p,n)<<endl;

	delete [] p;
	for(int i=0;i<=n;i++) delete [] m[i]; delete [] m;
}

int matrixChainMultiplication(int **m,int *p,int n){
	for(int i=1;i<=n;i++) m[i][i] = 0;

	int minimum = 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] = Sentinel;
			for(int k=i;k<j;k++){
				m[i][j] = min(m[i][k]+m[k+1][j]+p[i-1]*p[k]*p[j],m[i][j]);
				minimum = (minimum,m[i][j]);
			}
		}
	}
	return minimum;
}

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;
}