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 main(int argc, char const *argv[])
{
    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;
typedef long long ll;
typedef vector<vector<int> > vvi;
typedef vector<int> vi;
typedef vector<string> vs;
typedef pair<string, int> psi;
typedef pair<int, int> pii;
#define rep(i,s,n) for(int i = (s); i < (n); i++)
#define loop(i) for(int i = 0;true; i++)
#define all(x) (x).begin(), (x).end()
#define mn 1000000007
int main() {
	int N;
	cin >> N;
	vi A(N+1);
	vvi cost(N, vi(N,0));
	for (int i = 0; i < N; i++)
	{
		cin >> A[i] >> A[i + 1];
	}
	for (int i = 2; i <= N; i++)
	{
		for (int left = 0; left <= N-i; left++)
		{
			int right = left + i - 1;
			cost[left][right] =1e9;
			for (int k = left; k < right; k++)
			{
				cost[left][right] = min(cost[left][right], cost[left][k] +cost[k+1][right]+ A[left] * A[k+1] * A[right+1]);
			}
		}
	}
	cout << cost[0][N - 1] << endl;
};

C++: #include<iostream>
#include<algorithm>
#include<stdio.h>
#include<stdlib.h>
#include<string>
#include<vector>
#include<math.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
const long long mod = 1e9 + 7;

int main(){
    int n;
    cin >> n;
    int p[n+1], m[n+1][n+1];
    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 i = 2; i <= n; i++) for(int j = 1; j <= n - i + 1; j++){
        int k = j + i - 1;
        m[j][k] = (1 << 21);
        for(int l = j; l <= k - 1; l++) m[j][k] = min(m[j][k], m[j][l] + m[l + 1][k] + p[j - 1] * p[l] * p[k]);
    }
    cout << m[1][n] << 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=0; 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 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] + m[k + 1][j] + p[i - 1] * p[k] * p[j]);
			}
		}
	}
	cout << m[1][n] << endl;
	return 0;
}

C++: #include<iostream>
#include<algorithm>
#include<vector>
#include<stack>
#include<queue>
#include<list>
#include<string>
#include<cstring>
#include<cstdlib>
#include<cstdio>
#include<cmath>
using namespace std;

const int NIL = -1;
const int MAX = 200000001;
int m[101][101];
int p[101];

int main(void)
{
	int n;
	cin >> n;
	for (int i = 0; i < n; i++)
		cin >> p[i] >> p[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++) {
			int j = i + l - 1;
			m[i][j] = 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]);
		}
	}
	cout << m[1][n] << 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=0;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;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 <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(ri,n) for(int ri = (int)(n-1); ri >= 0; ri--)
#define rep2(i,x,n) for(int i = (int)(x); i < (int)(n); i++)
#define repit(itr,x) for(auto itr = x.begin(); itr != x.end(); itr++)
#define rrepit(ritr,x) for(auto ritr = x.rbegin(); ritr != x.rend(); ritr++)
#define ALL(n) begin(n), end(n)
using ll = long long;
using namespace std;

int main(){
  int n;
  cin >> n;
  vector<int> p(n+1);
  rep(i, n){
    int a, b;
    cin >> a >> b;
    if(i != 0) p.at(i+1) = b;
    else{
      p.at(0) = a;
      p.at(1) = b;
    }
  }
  vector<vector<ll>> dp(n, vector<ll>(n, 0));
  rep2(l, 1, n){
    rep(i, n - l){
      int j = i + l;
      dp.at(i).at(j) = LLONG_MAX;
      rep2(k, i, j){
        ll add = dp.at(i).at(k) + dp.at(k+1).at(j) + p.at(i) * p.at(k+1) * p.at(j+1);
        dp.at(i).at(j) = min(dp.at(i).at(j), add);
      }
    }
  }
  // rep(i, n){
  //   rep(j, n){
  //     printf("%9d ", (int)dp.at(i).at(j));
  //   }
  //   cout << endl;
  // }
  cout << dp.at(0).at(n-1) << endl;
  return 0;
}

C++: #include<iostream>
#include<algorithm>
using namespace std;
static const int N=100;

int main(){
  int n,i,l,k,p[N+1],m[N+1][N+1];
  cin>>n;
  for(i=1;i<=n;i++){
    cin>>p[i-1]>>p[i];
  }
  for(i=1;i<=n;i++)m[i][i]=0;
  for(l=2;l<=n;l++){
    for(i=1;i<=n-l+1;i++){
      int j=i+l-1;
      m[i][j]=(1<<21);
      for(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;
}