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 <cstdlib>
#include <vector>
using namespace std;

struct matrix_size{
	int row;
	int col;
};

int matrixchaincost(vector <matrix_size> &M){
	int n=M.size();
	vector < vector <int> > cost(n, vector <int> (n));
	vector < vector <matrix_size> > X(n, vector <matrix_size> (n));
	for (int i=0; i<n; i++){
		cost[i][i] = 0;
		X[i][i] = M[i];
	}

	for (int length=2; length<=n; length++){
		for (int i=0; i+length<=n; i++){
			int j = i+length-1;
			X[i][j].row = X[i][i].row;
			X[i][j].col = X[j][j].col;
			if (X[i][j-1].col != X[j][j].row){
				cout<<"error"<<endl;
				return NULL;
			}
			int k = i+1;
			int mincost = X[i][k-1].row * X[i][k-1].col * X[k][j].col + cost[i][k-1] + cost[k][j];
			k++;
			while (k<=j){
				int tmp = X[i][k-1].row * X[i][k-1].col * X[k][j].col + cost[i][k-1] + cost[k][j];
				if (tmp<mincost)
					mincost = tmp;
				k++;
			};
			cost[i][j] = mincost;
		}
	}
	return cost[0][n-1];
}

int main(void){
	int n;
	cin>>n;

	vector <matrix_size> M(n);

	for (int i=0; i<n; i++){
		cin>>M[i].row;
		cin>>M[i].col;
	}
	cout<<matrixchaincost(M)<<endl;
	return 0;
}

C++: #include<iostream>
#include<algorithm>

static const int N=100;

using namespace std;

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 <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repr(i, n) for (int i = (int)(n); i >= 0; i--)
#define REP(i, m, n) for (int i = (int)(m); i <= (int)(n); i++)
#define REPR(i, m, n) for (int i = (int)(m); i >= (int)(n); i--)
#define all(v) v.begin(), v.end()
typedef long long ll;
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

const int INF = 1001001001;

int n;
int p[110];
int dp[110][110];

int main(){
  cin >> n;
  REP(i, 1, n) cin >> p[i-1] >> p[i];

  memset(dp, INF, sizeof(dp));
  rep(i, n+1) dp[i][i] = 0;

  REP(l, 2, n){
    REP(i, 1, n-l+1){
      int j = i+l-1;
      REP(k, i, j-1){
        chmin(dp[i][j], dp[i][k]+dp[k+1][j]+p[i-1]*p[k]*p[j]);
      }
    }
  }

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

  return 0;
}

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

int mcm(int n,int p[]){
	int m[n+1][n+1]={0};
	for(int s=0;s<n;s++){
		for(int i=1,j=s+2;j<=n;i++,j++){
			m[i][j]=1<<30;
			for(int k=i;k<j;k++){
				int tmp=m[i][k];
				tmp+=m[k+1][j];
				tmp+=p[i-1]*p[k]*p[j];
				m[i][j]=min(m[i][j],tmp);
			}
		}
	}
	return m[1][n];
}

int main(){
	int n;
	cin >> n;
	int p[n+1];
	for(int i=0;i<n;i++){
		int n1,n2;
		cin >> n1 >> n2;
		p[i]=n1;
		if(i==n-1) p[i+1]=n2;
	}
	
	cout << mcm(n,p) << endl;
	return 0;
}

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

void fnInput(vector<int>& rvnMtrx)
{
  int nMaxSiz;
  cin >> nMaxSiz;
  rvnMtrx.resize(nMaxSiz + 1);

  for (int i = 0; i < rvnMtrx.size() - 1; ++i)
    cin >> rvnMtrx[i] >> rvnMtrx[i + 1];
}

int fnMtrxChainMultpl(vector<vector<int>>& rvvnDetDP, const vector<int>& cnrvnMtrx)
{
  for (int i = 1; i < cnrvnMtrx.size(); ++i)  rvvnDetDP[i][i] = 0;

  const int cnMaxSiz = cnrvnMtrx.size() - 1;
  for (int nDif = 1; nDif <= cnMaxSiz - 1; ++nDif)
    for (int nRow = 1; nRow <= cnMaxSiz - nDif; ++nRow)
    {
      int nCol = nRow + nDif;
      for (int nx = nRow; nx <= nCol - 1; ++nx)
        rvvnDetDP[nRow][nCol] =
          min(rvvnDetDP[nRow][nCol],
              rvvnDetDP[nRow][nx] + rvvnDetDP[nx + 1][nCol] 
                                  + cnrvnMtrx[nRow - 1] * cnrvnMtrx[nx] * cnrvnMtrx[nCol]);
    }
}

int main()
{
  cin.tie(0);
  ios::sync_with_stdio(false);
  vector<vector<int>> vvnDetDP; 
  vector<int> vnMtrx;

  fnInput(vnMtrx);
  vvnDetDP.resize(vnMtrx.size(), vector<int>(vnMtrx.size(), INT_MAX));

  fnMtrxChainMultpl(vvnDetDP, vnMtrx);
  cout << vvnDetDP[1][vnMtrx.size() - 1] << endl;
  return 0;
}

C++: #include <stdio.h>
#include <algorithm>

using namespace std;


int main(){
	int n,minimum,tmp;
	scanf("%d",&n);
	int table[n][n];
	int data[n][2];

	for(int i=0;i<n;i++){
		for(int k=0;k<n;k++)table[i][k] = 0;
		scanf("%d %d",&data[i][0],&data[i][1]);
	}

	for(int i=n-2;i>=0;i--){
		for(int k=0;k<=i;k++){
			if(i==n-2){
				table[n-i-1][k] = data[k][0]*data[k][1]*data[k+1][1];
		}else{
				minimum = 2147483647;
				for(int p=0;p<=n-i-2;p++){
					tmp=(table[p][k]+table[n-i-p-2][k+p+1])+(data[k][0]*data[k+p][1]*data[k+n-i-1][1]);
					minimum = min(minimum,tmp);
				}
				table[n-i-1][k] = minimum;
			}
		}
	}

	printf("%d\n",table[n-1][0]);

    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 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 <bits/stdc++.h>
using namespace std;
using ll = long long;

signed
main(){
		int N;
		cin >> N;
		vector<ll> a(N+1);
		for(int i=0;i<N;i++){
				cin >> a[i] >> a[i+1];
		}
	
		vector<vector<ll> > m(N+1, vector<ll>(N+1,INT_MAX));

		for(int i=0;i<=N;i++)
				m[i][i] = 0;
		for(int i=0;i<N;i++)
				m[i][i+1] = 0;


		for(int sa=2;sa<=N;sa++){
				for(int b=0;b<=N-sa;b++){
						int e = b + sa;
						for(int med=b;med<=e;med++){
								m[b][e] = min(m[b][e], m[b][med] + m[med][e] + a[b]*a[med]*a[e]);
						}
				}
		}
		cout << m[0][N] << endl;

}