Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	fmt.Println(resolve(parseProblem()))
}

type matrixSize struct{ row, col int }

func calcNum(i, j matrixSize) int {
	return i.row * j.col * i.col
}

func parseProblem() (int, []matrixSize) {
	n := scanInt(sc)
	sizes := make([]matrixSize, n)
	for i := 0; i < n; i++ {
		sizes[i] = matrixSize{row: scanInt(sc), col: scanInt(sc)}
	}
	return n, sizes
}

var dp [][]int

func initDP(n int) {
	dp = make([][]int, n+1)
	for i := 0; i < len(dp); i++ {
		dp[i] = make([]int, n+1)
		for j := 0; j < len(dp[i]); j++ {
			dp[i][j] = math.MaxInt64
		}
	}
}

func resolve(n int, sizes []matrixSize) int {
	// TODO 復習
	initDP(n)
	_rec(sizes, 0, n)
	return dp[0][n]
}

func _rec(sizes []matrixSize, l, r int) int {
	if dp[l][r] != math.MaxInt64 {
		return dp[l][r]
	}
	if r-l <= 1 {
		dp[l][r] = 0
		return 0
	}
	num := math.MaxInt64
	for i := l + 1; i < r; i++ {
		v := _rec(sizes, l, i) + _rec(sizes, i, r) + calcNum(matrixSize{sizes[l].row, sizes[i].row}, matrixSize{sizes[i].row, sizes[r-1].col})
		if v < num {
			num = v
		}
	}
	dp[l][r] = num
	return dp[l][r]
}

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

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


static const int N = 100;

int m[N+1][N+1];
int main()
{
    int n,p[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;
    int i;
    for(int l=2;l<=n;l++)
    {
        for(int i=1;i<=n-l+1;i++)
        {
            int j=i+l-1;
            m[i][j]=(9999999);
            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 << "l i j k m[i][j]:" <<l<<" " << i << " " << j << " "<<k<<" "<<m[i][j]<<endl;
            }
        }
    }
    cout <<m[1][n] << endl;

    return 0;
}

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

struct Matrix{
  int x, y;
};

int dp[111][111];
vector<Matrix> v;
Matrix matrix[111][111];

int main(){

  int n, r, c;

  cin >> n;

  for(int i = 0; i < n; i++){
    cin >> r >> c;
    v.push_back((Matrix){r,c});
  }

 
  for(int i = 0; i < n; i++) dp[i][i] = 0;
  for(int i = 1; i < n; i++){
    for(int j = 0; j < n - i; j++){
      int s = j + i;
      dp[j][s] = INT_MAX;
      for(int l = j; l < s; l++){
	dp[j][s] = min(dp[j][s],dp[j][l] + dp[l+1][s] + v[j].x * v[s].y * v[l].y);
      }
    }
  }
  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 <bits/stdc++.h>
#define _GLIBCXX_DEBUG
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rrep(i, n) for (int i = 1; i < (n+1); ++i)
using namespace std;
using ll = long long;
const int INF = +100100100;
// typedef pair<int,int> P;

vector<int>P;

int dp(int n){
    vector<vector<int>> D(n,vector<int>(n));
    rep(j,n){
        for(int i = j;i>=0;--i){
            if(i==j)D[i][j]=0;
            else{
                int mini = INF;
                for(int k = i;k<j;++k){
                    int rel = D[i][k]+D[k+1][j]+P[i]*P[k+1]*P[j+1];
                    mini = min(mini,rel);
                }
                D[i][j]=mini;
            }
        }
    }
    return D[0][n-1];
}

int main(){
    int n;
    cin>>n;
    rep(i,n){
        int x,y;cin >> x>>y;
        if(i==0){
            P.push_back(x);
            P.push_back(y);
        }
        else{
            P.push_back(y);
        }
    }
    cout << dp(n) << endl;
    return 0;
}

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

const int INF = INT_MAX/3;
typedef vector<int> vi;
typedef pair<int,int> pii;

int main(){
    int n;cin>>n;
    vector<pii> p(n+1);
    for(int i=0;i<n;i++) cin>>p[i].first>>p[i].second;

    vector<vi> mat(n+1,vi(n+1,INF));    //mat[i][j] : Mi*...*Mj???????°??????°
    for(int i=0;i<n;i++) mat[i][i] = 0;

    for(int sz=2;sz<=n;sz++){
        /*
         * mat[i][j] = min( mat[i][k]+mat[k+1][j]+Mi.first*Mk+1.first*Mk+1.second )
         */
      //  cout << "size = " << sz << endl;
        for(int i=0;i<=n-sz;i++){

            int j = i + sz - 1;

       //     cout << i << " : " << j << endl;

            for(int k=i;k<=j-1;k++){
        //        cout << i << ":" << j << ":" << mat[i][k] << ":" << mat[k+1][j] << endl;
                int tmp = mat[i][k] + mat[k+1][j] + p[i].first * p[k+1].first * p[j].second;
                //cout << tmp << endl;
                mat[i][j] = min(mat[i][j] , mat[i][k] + mat[k+1][j] + p[i].first * p[k+1].first * p[j].second);
            }
        }
    }

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

    cout << mat[0][n-1] << endl;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,s,n) for(int i = (s); i < (n); i++)

int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(18);
  
  int n;
  cin >> n;
  int dp[n+1][n+1];
  rep(i, 1, n+1) dp[i][i] = 0;
  int p[n+1];
  rep(i, 0, n) cin >> p[i] >> p[i+1];
  
  rep(l, 2, n+1) {
    rep(i, 1, n-l+2) {
      int j = i+l-1;
      dp[i][j] = 1000000007;
      rep(k, i, j) {
        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] << "\n";
}

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 <vector>
#include <limits>

using namespace std;

// M1, M2, M3, ... , Mn-1, Mn
// M[i,j] = 0 if i = j
// M[i,j] = min { M[i,j] = M[i,k] + M[k+1,j] + p_{i-1} * p_k * p_j } where i <= k < j

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

    vector<int> P(n+1);
    for (int i = 1; i < n+1; ++i) {
        cin >> P[i-1] >> P[i];
    }

    int M[n+1][n+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) {
            int j = i + l - 1;
            M[i][j] = std::numeric_limits<int>::max();
            for (int k = i; k <= j - 1; ++k) {
                int q = M[i][k] + M[k+1][j] + P[i-1] * P[k] * P[j];
                M[i][j] = min(M[i][j], q);
            }
        }
    }
    cout << M[1][n] << endl;

    return 0;
}