Go: package main

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

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	v, _ := strconv.Atoi(sc.Text())
	return v
}

func min(x, y int) int {
	if x > y {
		return y
	}
	return x
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n := nextInt(sc)

	P := make([]int, n+1)
	for i := 1; i <= n; i++ {
		l := nextInt(sc)
		P[i-1] = l
		m := nextInt(sc)
		P[i] = m
	}

	matrix := make([][]int, n+1)
	for i := 0; i < n+1; i++ {
		matrix[i] = make([]int, n+1)
	}

	for l := 2; l <= n; l++ {
		for i := 1; i <= n - l + 1; i++ {
			j := i + l - 1
			matrix[i][j] = (1 << 21)
			for k := i; k <= j-1; k++ {
				matrix[i][j] = min(matrix[i][j], matrix[i][k] + matrix[k+1][j] + P[i-1] * P[k] * P[j])
			}
		}
	}
	fmt.Println(matrix[1][n])
}

C++: #include <bits/stdc++.h>
#define INF 1000000001
using namespace std;
typedef long long ll;

int main()
{
  ll N;
  cin >> N;
  vector<pair<ll, ll>> M(N);
  for (ll i = 0; i < N; ++i)
  {
    cin >> M.at(i).first >> M.at(i).second;
  }
  vector<vector<ll>> dp(N, vector<ll>(N, INF));
  for (ll i = 0; i < N; ++i)
  {
    dp.at(i).at(i) = 0;
  }
  for (ll i = 0; i < N - 1; ++i)
  {
    dp.at(i).at(i + 1) = M.at(i).first * M.at(i).second * M.at(i + 1).second;
  }

  for (ll width = 1; width < N; ++width)
  {
    for (ll l = 0; l < N - width; ++l)
    {
      ll r = l + width;
      for (ll m = l + 1; m < r + 1; ++m)
      {
        dp.at(l).at(r) = min(dp.at(l).at(r), dp.at(l).at(m - 1) + dp.at(m).at(r) + M.at(l).first * M.at(m - 1).second * M.at(r).second);
      }
    }
  }
  cout << dp.at(0).at(N - 1) << endl;
  // for (ll i = 0; i < N; ++i)
  // {
  //   for (ll j = 0; j < N; ++j)
  //   {
  //     cout << dp.at(i).at(j) << ' ';
  //   }
  //   cout << endl;
  // }
}

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 << "0" << 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++: //?????????B 
#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;
#define INF (1 << 20)
int main()
{
    int n;
    cin >> n;
    int p[101];

    // i番目の行列は p[i]*p[i+1]
    for (int i = 0; i < n; i++)
    {
        cin >> p[i] >> p[i + 1];
    }

    // m[i][j] : i番目からj番目までの部分積でのスカラー乗算の最小回数
    //      i = 0,1, ... , n-1
    // m[i][i] := 0
    // m[i][j] = min_{i <= k < j} m[i][k] + m[k+1][j] + p[i]*p[k+1]*p[j+1]
    //      l = 2,3, ... , n
    //      i = 0,1, ... , n-l
    //          j = i+l-1
    //      k = i, i+1, ... , j-1
    // l = j-i
    int m[101][101];
    for (int i = 0; i < n; i++)
    {
        m[i][i] = 0;
    }

    for (int l = 2; l <= n; l++)
    {
        for (int i = 0; i <= n-l; i++)
        {
            int j = i + l - 1;
            int minv=INF;
            for (int k = i; k < j; k++)
            {
                minv = min(minv, m[i][k] + m[k + 1][j] + p[i] * p[k + 1] * p[j + 1]);
            }
            m[i][j] = minv;
            
            // cout << "m[ " << i<<" ][ "<<j<< " ] = " << minv << endl;
        }
    }
    cout << m[0][n-1] << endl;
    return 0;
}

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

static const int N=100;

//求解矩阵链乘法的最优解
//p 用于存储矩阵的行和列的
//dp[i][j] 表示从矩阵i乘到矩阵j的最小乘法次数

int main(){
    int n;
    int p[N+1],dp[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++){
        dp[i][i]=0;
    }
    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<<21);//取一个很大的值
            for(int k=i;k<=j-1;k++){
                dp[i][j]=min(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<algorithm>
#include<iostream>

using namespace std;
typedef long long ll;

const int MAX = 100;



int main() {


	int n, p[MAX + 1], m[MAX + 1][MAX + 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 calcLen = 2;calcLen <= n;calcLen++) {

		for (int st = 1;st <= n - calcLen + 1;st++) {
			int ed = st + calcLen - 1;
			m[st][ed] = (1 << 21);

			for (int divP = st;divP <= ed-1;divP++) {
				m[st][ed] = min(m[st][ed], m[st][divP] + m[divP + 1][ed] + p[st - 1] * p[divP] * p[ed]);
			}
		}
	}
	cout << m[1][n] << endl;

	return 0;
}

C++: #include<iostream>
#define MAX 99999999;
using namespace std;
int p[102];
int mcm[102][102];
int n;
int min(int x,int y) {
	int m = MAX;
	int cost = 0;
	for (int j = x; j < y; j++) {
		cost = mcm[x][j] + mcm[j + 1][y] + p[x-1]*p[j]*p[y];
		if (cost < m) {
			m = cost;
		}
	}
	return m;
}
int calMcm() {
	for (int j = 2; j <= n; j++) {
		for (int i = 1; i <= n-j+1; i++) {
			mcm[i][j+i-1] = min(i, j+i-1);
		}
	}
	return mcm[1][n];
}
int main() {
	int t;

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

	/*for (int i = 0; i <= n; i++) {
		cout << p[i] << " ";
	}
	cout << endl;*/

	cout << calMcm() << endl;
}