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 <vector>
using namespace std;

static const int INF = 1000000000;

int main() {
    int n;
    cin >> n;
    vector<int> p(n + 1);
    vector< vector<int> > dp(n + 1, vector<int>(n + 1));
    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] = INF;
            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<iostream>
#include<algorithm>
#include<string>

using namespace std;

static const int N = 100;
static const int INF = (1 << 21);

int main() {
    int n;
    int p[N + 1];
    int m[N + 1][N + 1];

    cin >> n;

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

    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] = INF;
            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]);
            }
        }
    }

    cout << m[1][n] << endl;
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define int long long
const int INF = 1e9;

signed main(){
  int N; cin >> N;
  vector<vector<int> > dp(N + 1, vector<int> (N + 1, 0));
  vector<int> r(N + 1);
  for(int i = 1; i <= N; i++) cin >> r[i - 1] >> r[i];
  for(int l = 1; l < N; l++){
    for(int i = 1; i <= N - l; i++){
      int j = l + i;
      dp[i][j] = INF;
      for(int k = i; k < j; k++){
        dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j] + r[i - 1] * r[k] * r[j]);
      }
    }
  }
  cout << dp[1][N] << endl;
}

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

const int MAX = 1 << 30;

struct Matrix {
  Matrix(int r,int c){
    row = r;
    col = c;
  }
  int row,col;
};

int dp[100][100];

int rec(int left, int right, vector<Matrix>& M)
{
  if(left==right){ return 0; }
  
  if(dp[left][right]<MAX){ return dp[left][right]; }
  
  if(right-left==1){
    dp[left][right] = M[left].row * M[left].col * M[right].col;
    return dp[left][right];
  }
  
  int answer = MAX;
  for(int mid=left;mid<right;mid++){
    //////////////
    //int a = rec(left,mid,M)+rec(mid+1,right,M) + M[mid].row * M[mid].col * M[mid+1].col;
    //cout << "left:" << left << ",mid:" << mid << ",right:" << right << ",answer:" << a << endl;
    //////////////
    answer = min(answer,rec(left,mid,M)+rec(mid+1,right,M) + M[left].row * M[mid].col * M[right].col);
  }
  
  dp[left][right] = answer;
  return dp[left][right];
}


int main(void){
    // Your code here!
    int n;
    cin >> n;
    
    if(n==1){
      cout << 0 << endl;
      return 0;
    }
    
    vector<Matrix> M;
    for(int i=0;i<n;i++){
      int row,col;
      cin >> row >> col;
      M.push_back(Matrix(row,col));
    }
    
    for(int i=0;i<n;i++){
      for(int j=0;j<n;j++){
        dp[i][j] = MAX;
      }
    }
    
    rec(0,n-1,M);

    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;
}