Go: package main

/*
連鎖行列積
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"math"
	"os"
	"strconv"
	"strings"
)

func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

type mem *[][]int

func main() {
	scanner := makeScanner(1024)
	n := eGetInt(scanner)
	p := make([]int, n+1)
	for i := 0; i < n; i++ {
		rowcol := eGetInts(scanner)
		p[i] = rowcol[0]
		p[i+1] = rowcol[1]
	}
	m := make([][]int, n)
	for i := 0; i < n; i++ {
		m[i] = make([]int, n)
	}
	// 初期値の格納
	for i := 0; i < n; i++ {
		for j := i; j < n; j++ {
			if i == j {
				m[i][j] = 0 //  同じ行列へのコストは当然0
			} else {
				m[i][j] = math.MaxInt64
			}
		}
	}

	// num : 行列の数. num == 1の場合は初期値0を格納ずみ
	for num := 2; num <= n; num++ {
		// s : スタート行列番号
		for s := 0; s+num <= n; s++ {
			// t : 終了行列番号
			t := s + num - 1
			// k : 仕切
			for k := s; k < t; k++ {
				m[s][t] = min(m[s][t], m[s][k]+m[k+1][t]+p[s]*p[k+1]*p[t+1])
			}
		}
	}
	fmt.Println(m[0][n-1])
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}

// func min(a []int) int {
// 	m := a[0]
// 	for _, v := range a {
// 		if v < m {
// 			m = v
// 		}
// 	}
// 	return m
// }

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

C++: #include <iostream>
#include <iomanip>
#include <algorithm>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <cstdio>
#include <cstdlib>
#include <functional>
#include <sstream>
#include <string>
#include <utility>
#include <map>
#include <memory>
#include <set>
#include <vector>
#include <deque>
#include <list>
#include <stack>
#include <queue>

using namespace std;

class MCMult
{
public:
  vector<vector<int>> mat;
  int solve();
};

int MCMult::solve()
{
  int ms = mat.size();
  vector<vector<int>> dp(ms, vector<int>(ms, 0));

  for ( auto i = 0; i < ms - 1; ++i )
    dp[i][i+1] = mat[i][0] * mat[i][1] * mat[i+1][1];

  for ( auto k = 2; k < ms; ++k )
    {
      for ( auto i = 0; i + k < ms; ++i )
        {
          int ret = dp[i+1][i+k] + mat[i][0] * mat[i][1] * mat[i+k][1];
          ret = min( ret, dp[i][i+k-1] + mat[i+k][0] * mat[i+k][1] * mat[i][0]);
          
          for ( auto j = i + 1; j < i + k - 1; ++j )
            {
              ret = min( ret, dp[i][j] + dp[j+1][i+k] + mat[i][0] * mat[j][1] * mat[i+k][1]);
            }
          dp[i][i+k] = ret;
        }
    }

  cout << dp[0][ms-1] << endl;
  
  return 0;
}

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

  MCMult m;

  for ( int i = 0; i < n; ++i )
    {
      int x;
      vector<int> v;
      
      cin >> x;
      v.push_back( x );
      cin >> x;
      v.push_back( x );
      
      m.mat.push_back( v );
    }
  
  m.solve();

  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i,n) for(int i=0;i<(n);i++)
#define rep2(i,n) for(int i=1;i<=(n);i++)
#define rep3(i,i0,n) for(int i=i0;i<(n);i++)
#define pb push_back
#define mod 1000000007
const ll INF = 1LL << 60;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
ll gcd(ll a, ll b) {return b?gcd(b,a%b):a;}
ll lcm(ll a, ll b) {return a/gcd(a,b)*b;}
#define all(x) x.begin(), x.end()
#define mp make_pair
bool compare(pair<int, int> a, pair<int, int> b) {
    if(a.first != b.first){
        return a.first < b.first;
        
    }else{
        return a.second < b.second;
    }
}


bool In_map(ll y,ll x,ll h,ll w){
    if(y<0 || x<0 || y>=h || x>=w){
        return 0;
    }else{
        return 1;
    }
}
const vector<ll> dx{1,0,-1,0};
const vector<ll> dy{0,1,0,-1};
int main() {
    ll n;
    cin >> n;
    vector<ll> r(n);
    vector<ll> c(n);
    rep(i,n){
        cin >> r[i] >> c[i];
    }

    vector<vector<ll>> dp(n,vector<ll>(n,INF));
    rep(i,n){
        dp[i][i] = 0;
    }
    rep(i,n){
        rep(j,n-i-1){
            rep(k,i+1){
                chmin(dp[j][j+i+1],dp[j][j+k]+dp[j+k+1][j+i+1] + r[j]*c[j+k]*c[j+i+1]);
                //chmin(dp[i][j],dp[i][i+k]+dp[i+k+1][j] + r[i]*c[i+k]*c[j]);
            }
        }

    }

    cout <<dp[0][n-1]<<endl;;
    return 0;
    

}

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

using namespace std;

struct matrix {
  int r;
  int c;
};

// 連鎖行列積問題
int main() {
  vector<matrix> mat;
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    int tmp1,tmp2;
    cin >> tmp1 >> tmp2;
    matrix m = {tmp1, tmp2};
    mat.push_back(m);
  }
  
  int** memo = new int*[n];
  for (int s = 0; s < n; s++) {
    memo[s] = new int[n];
  }

  for (int l = 1; l < n; l++) {
    for (int s = 0; s < n; s++) {
      if (s + l >= n) {
        break;
      }
      
      int minval = (1 << 21);
      int sum = 0;
      for (int i = 0; i < l; i++) {
        sum = memo[s][s+i] + memo[s+i+1][s+l];
        matrix m1 = mat[s];
        matrix m2 = mat[s+i];
        matrix m3 = mat[s+l];

        sum += m1.r * m2.c * m3.c;

        minval = min(minval, sum);
      }
      memo[s][s+l] = minval;
    }
  }

  cout << memo[0][n-1] << endl;
  return 0;
}

C++: #include<iostream>
#include<cmath>
#include<algorithm>
#include<vector>
#include<queue>

using namespace std;

vector<int> R;
vector<int> C;
vector<vector<int>> dp;

long long int rec(int l,int r){
  if(dp[l][r]!=-1) return dp[l][r];
  if(abs(r-l)<=1)return 0;
  long long int res=10000007;
  for(int mid=l+1;mid<r;mid++){
    res=min(res,rec(l,mid)+rec(mid,r)+R[l]*C[mid-1]*C[r-1]);
  }
  return dp[l][r]=res;
}

int main(){

  int n;
  cin >> n;

  dp.resize(n+1);
  for(int i=0;i<n+1;i++)dp[i].resize(n+1);

  for(int i=0;i<n+1;i++){
    for(int j=0;j<n+1;j++){
      dp[i][j]=-1;
    }
  }

  R.resize(n);
  C.resize(n);
  for(int i=0;i<n;i++)cin >> R[i] >> C[i];

  int c=rec(0,n);

  cout << c << endl;


}