Go: package main

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

type Matrix struct {
	r int // num of row
	c int // num of column
}

type Range struct {
	start int // index, inclusive
	end   int // index, inclusive
}

func (r Range) length() int {
	return r.end - r.start + 1
}

func calcMultiplication(x, y Matrix) (Matrix, int) {
	if x.c != y.r {
		panic("cannnot calculate")
	}
	return Matrix{x.r, y.c}, x.r * y.c * x.c
}

func calcMinMatrixChainMultiplication(matrices []Matrix, r Range, memo map[Range]int) (Matrix, int) {
	if v, ok := memo[r]; ok {
		return Matrix{matrices[r.start].r, matrices[r.end].c}, v
	}
	if r.length() == 0 {
		panic("must not be empty")
	} else if r.length() == 1 {
		return matrices[r.start], 0
	}

	var minCount int = math.MaxInt32

	for i := 0; i < r.length()-1; i++ {
		formerRange := Range{r.start, r.start + i}
		latterRange := Range{r.start + i + 1, r.end}
		matF, countF := calcMinMatrixChainMultiplication(matrices, formerRange, memo)
		matL, countL := calcMinMatrixChainMultiplication(matrices, latterRange, memo)
		_, countFL := calcMultiplication(matF, matL)
		count := countF + countL + countFL
		if count < minCount {
			minCount = count
		}
	}
	memo[r] = minCount
	return Matrix{matrices[r.start].r, matrices[r.end].c}, minCount
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n, _ := nextInt(sc)
	matrices := make([]Matrix, n)
	for i := 0; i < n; i++ {
		r, _ := nextInt(sc)
		c, _ := nextInt(sc)
		matrices[i] = Matrix{r, c}
	}
	memo := make(map[Range]int)
	_, resultCount := calcMinMatrixChainMultiplication(matrices, Range{0, len(matrices) - 1}, memo)
	fmt.Println(resultCount)
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

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;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0; i<n; i++)
typedef long long ll;
typedef long long unsigned int llu;
ll MOD = 1000000007;
ll INF = 1000000009;

int a[110];
int b[110];
int dp[110][110];
/*
dp[i][j]:行列i~jまでの乗算回数の最小値
dp[i][j]=min(dp[i-1][j]+(a[i-1]*b[i-1]*[b[j]])), dp[i][j+1]+(a[i]*a[j+1]*b[j+1]))
*/

void solve(){

    int n;
    cin >> n;
    rep(i,n){
      cin >> a[i] >> b[i];
    }
    rep(i,110){
      rep(j,110){
          dp[i][j]=0;
      }
    }
    
    for(int i=1; i<n; i++){
        dp[i-1][i]=a[i-1]*b[i-1]*b[i];
    }
    

    for(int i=2; i<n; i++){
        for(int j=0; j<n-i; j++){
            int ans = INF;
            int x = j;
            int y = i+j;
            for(int k=0; k<y-x; k++){
                ans = min(int(ans), int(dp[x][x+k]+dp[x+k+1][y]+a[x]*b[x+k]*b[y]));
            }
            dp[j][i+j]=ans;
        }
    }

    /*
    rep(i,n){
        rep(j,n){
            cout << dp[i][j] << " ";
        }
        cout << endl;
    }
    */

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

}


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

C++: //
//  main.cpp
//  longest_common_subsequence
//
//  Created by ???????????? on 2017/10/17.
//  Copyright ?? 2017 ????????????. All rights reserved.
//

#include <iostream>
#include <stdio.h>
#include <string.h>

using namespace std;

char X[1005];
char Y[1005];

void lcs(){
    size_t m = strlen(X);
    size_t n = strlen(Y);
    int c[m+1][n+1];
    c[0][0] = 0;
    for (int i = 1; i <= m; i++) c[i][0] = 0;
    for (int j = 1; j <= n; j++) c[0][j] = 0;
    for (int i = 1; i <= m; i++){
        for(int j = 1; j <= n; j++){
            if (X[i] == Y[j]){
                c[i][j] = c[i-1][j-1]+1;
            }
            else if(c[i-1][j] >= c[i][j-1]){
                c[i][j] = c[i-1][j];
            }
            else{
                c[i][j] = c[i][j-1];
            }
        }
    }
    cout << c[m][n] << endl;
//    cout << c[m+1][n+1] << endl;
}

int main(int argc, const char * argv[]) {
    int n, i;
    scanf("%d", &n);
    for (i = 0; i < n; i++){
        scanf("%s", X);
        scanf("%s", Y);
        lcs();
    }
//    std::cout << "Hello, World!\n";
    return 0;
}

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

int main() {

  int n;
  cin >> n;

  // l × m 行列と m × n 行列の積では、l × m × n 回の計算が生じる
  // M_i を p_i-1 × p_i 行列とすると、M_i × M_i+1 の計算回数は、p_i-1 × p_i × p_i+1 となる
  // M_1, M_2, M_3 が与えられたとき、((M_1 × M_2) × M_3) と (M_1 × (M_2 × M_3)) の計算量が少ない方を選択する

  // p:M_i を p_i-1 × p_i 行列とする
  vector<int> p(n+1);
  for (int i = 1; i <= n; i++) {
    cin >> p[i-1] >> p[i];
  }

  // cost[i][j]:M_i から M_j までの最小計算量
  vector<vector<int>> cost(n+1, vector<int> (n+1));

  // i から l 個まで調べる
  for (int l = 2; l <= n; l++) {
    for (int i = 1; i <= n - l + 1; i++) {
      // i から l までの個数
      int j = i + l - 1;
      // 大きい数値を入れておく
      cost[i][j] = 1000000007;
      // i から j 回調べる
      for (int k = i; k < j; k++){
        cost[i][j] = min(cost[i][j], cost[i][k] + cost[k+1][j] + p[i - 1] * p[k] * p[j]);
      }
    }
  }

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

  return 0;

}