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

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

typedef long long ll;
typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef pair<int, int> P;
typedef tuple<int,int,int> tpl;

#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define SORT(c) sort((c).begin(),(c).end())
#define REVERSE(c) reverse((c).begin(),(c).end())
#define LB(a,x) lower_bound((a).begin(), (a).end(), x) - (a).begin()
#define UB(a,x) upper_bound((a).begin(), (a).end(), x) - (a).begin()

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define RFOR(i,a,b) for(int i=(a)-1;i>=(b);--i)
#define RREP(i,n) RFOR(i,n,0)

#define en "\n"

const double EPS = 1e-9;
const double PI  = acos(-1.0);
const int INT_INF = 2147483647;
const long long LL_INF = 1LL<<60;
const long long MOD = 1000000007;

#define CLR(a) memset((a), 0, sizeof(a))

#define dump(x)  cerr << #x << " = " << (x) << endl;
#define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }

ll dp[101][101];
vector<ll> R(101), C(101);

ll rec(int l, int r){
    if(dp[l][r] != -1) return dp[l][r];
    if(r-l == 2) return dp[l][r] = R[l]*R[r-1]*C[r-1];
    if(r-l < 2) return dp[l][r] = 0;

    ll res = LL_INF;
    FOR(i,l+1,r){
        chmin(res, R[l]*R[i]*C[r-1]+(rec(l,i)+rec(i,r)));
    }
    return dp[l][r] = res;
}

int main(void){
    ll n; cin >> n;
    REP(i,n) cin >> R[i] >> C[i];
    REP(i,n+1)REP(j,n+1) dp[i][j] = -1;
    //REP(i,n+1)FOR(j,i+2,n+2) dp[i][j] = LL_INF;
    ll ans = rec(0,n);
    cout << ans << en;
    return 0;
}

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

int mcm(int N, vector<int>& p, vector<vector<int>>& M)
{
	for (int l = 1; l < N; l++)
	{
		for (int i = 1; i <= N - l; i++)
		{
			int j = i + l;
			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]);
			}
		}
	}
	return M[1][N];
}

int main(void)
{
	int N;
	cin >> N;
	vector<int> p;
	vector<vector<int>> M(N + 1, vector<int>(N + 1, 0));

	for (int i = 0; i < N; i++)
	{
		int x, z;
		cin >> x >> z;
		if (!i) p.push_back(x);
		p.push_back(z);
	}

	cout << mcm(N, p, M) << endl;

	return 0;
}

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

using namespace std;

const int kMax = 100 + 5;

int n;
int num[kMax], dp[kMax][kMax];

int main() {
    scanf("%d", &n);
    for(int i = 1;i <= n;++ i) scanf("%d%d", &num[i-1], &num[i]);
    for(int l = 2;l <= n;++ l) {
        for(int i = 1;i <= n - l + 1;++ i) {
            int j = i + l - 1;
            dp[i][j] = (1 << 30);
            for(int k = i;k < j;++ k) dp[i][j] = min(dp[i][j], dp[i][k] + dp[k+1][j] + num[i-1] * num[k] * num[j]);
        }
    }
    printf("%d\n", dp[1][n]);
    return 0;
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <cstdio>
#include <cstdlib>
#include <string>
#include <iostream>
#include <climits>

using namespace std;

int main() {
	int i, j, k, to, min, temp_result;
	int n;
	int r[100], c[100];
	int result[100][100];
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> r[i] >> c[i];
		result[i][i] = 0;
	}
	
	i = 0;
	j = 1;
	to = n - 2;
	while (j <= n - 1) {
		while (i <= to) {
			//computation of result[i][i+j]
			min = INT_MAX;
			k = i;
			while (k <= i + j - 1) {
				temp_result = c[k] * r[i] * c[i + j] + result[i][k] + result[k + 1][i + j];
				if (temp_result < min) {
					min = temp_result;
				}
				k++;
			}
			result[i][i + j] = min;
			i++;
		}
		i = 0;
		j++;
		to--;
	}
	printf("%d", result[0][n - 1]);
}

C++: #include<iostream>
#include<cstdio>
#define INT_MAX 100000000
using namespace std;
int index;
int mm[1000][1000];
int mine = INT_MAX;

void solve(int p[]){
  int n = index-1,j,q;
  for(int i=1;i<=n;i++)mm[i][i]=0;
  for(int l=2;l<=n;l++){
    for(int i=1;i<=n-l+1;i++){
      j = i+l-1;
      mm[i][j] = INT_MAX;
      for(int k=i;k<=j-1;k++){
	q = mm[i][k] + mm[k+1][j] + p[i-1]*p[k]*p[j];
	if(q<mm[i][j]){
	  mm[i][j] = q;
       
	}

      }
    }
  }




}

int main(){
  int p[1000],a,b;
  scanf("%d",&index);
  //for(int i=0;i<=index;i++)for(int j=0;j<=n;j++)mm[i][j] = INT_MAX;
  for(int i=0;i<index;i++){
    scanf("%d %d",&a,&b);
    p[i] = a;
    if(i == index-1)p[i+1] = b;
  }

  index = index+1;
  solve(p);
 
  printf("%d\n",mm[1][index-1]);
  return 0;
}

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

int n;

int main(void) {

    cin >> n;
    int m[n + 1][n + 1] = {};
    int p[n + 1] = {}; // p[i - 1] x p[i]の行列を表す

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

    // 範囲が1の場合は計算しないので0
    for (int i = 1; i <= n; ++i) {
        m[i][i] = 0;
    }

    // l    : 対象とする行列の個数
    // i    : スタート地点
    // j    : ゴール地点
    // k    : 括弧を切るポイント
    for (int l = 2; l <= n; ++l) {
        for (int i = 1; i <= n - l + 1; ++i) {
            int j = i + l - 1;
            m[i][j] = INT32_MAX;
            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]);
            }
        }
    }

    // for (int i = 1; i <= n; ++i) {
    //     for (int j = i + 1; j <= n; ++j) {
    //         m[i][j] = INT32_MAX;
    //         for (int k = i; k < j; ++k) {
    //             // i ~ k, (k + 1) ~ jの行列計算
    //             // それまでの計算回数 + 新しい計算回数
    //             // それまでの計算回数はm[i][k] + m[k + 1][n]
    //             // 新しい計算回数は左の行 * 中間の列 * 右の列
    //             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;
}