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++: /*
 * chain_matrix.cpp
 *
 *  Created on: 2017/07/11
 *      Author: LitMc
 */

//#define MYDEBUG
#include <bits/stdc++.h>

#ifdef MYDEBUG
#define dbp(x) cout<<#x<<": "<<x<<endl
#define dbp2(x,y) cout<<#x<<","<<#y<<": "<<x<<","<<y<<endl
#define dbp3(x,y,z) cout<<#x<<","<<#y<<","<<#z<<": "<<x<<","<<y<<","<<z<<endl
#define dbp4(w,x,y,z) cout<<#w<<","<<#x<<","<<#y<<","<<#z<<": "<<w<<","<<x<<","<<y<<","<<z<<endl
#define ifcin(x) std::ifstream cin(x)
#else
#define dbp(x)
#define dbp2(x,y)
#define dbp3(x,y,z)
#define dbp4(w,x,y,z)
#define ifcin(x)
#endif
#define ll long long
#define ull unsigned long long
#define all(x) x.begin(), x.end()
#define rep(i, from, to) for(int i=from; i<to; ++i)
#define REP(i, from, to) for(int i=from; i<=to; ++i)
#define EPS = 1e-14;
using std::vector;
using std::cout;
using std::cin;
using std::endl;
using std::max;
using std::min;
using std::swap;
using std::string;
using std::fill;
using std::pair;
using std::sort;
using std::reverse;
using std::pair;
using std::greater;
using std::priority_queue;
using std::ostream;

template<typename T>
ostream& operator<<(ostream& out, const vector<vector<T> >& v) {
  for (size_t i = 0; i < v.size(); ++i) {
    out << v[i] << endl;
  }
  return out;
}

template<typename T>
ostream& operator<<(ostream& out, const vector<T>& v) {
  out << "[";
  size_t last = v.size() - 1;
  for (size_t i = 0; i < v.size(); ++i) {
    out << v[i];
    if (i != last) {
      out << ",";
    }
  }
  out << "]";
  return out;
}
template<typename T1, typename T2>
ostream& operator<<(ostream& out, const pair<T1, T2>& p) {
  out << "(" << p.first << ", " << p.second << ")";
  return out;
}

typedef pair<int, int> P;
bool cmp(const P &p1, const P &p2) {
  if (p1.first == p2.first) {
    return p1.second > p2.second;
  } else {
    return p1.first < p2.first;
  }
}
typedef pair<int, int> P;
static const int MAX_N = 110;
static const int INF = 100000000;
int n, r, c;
P M[MAX_N];
int dp[MAX_N][MAX_N];

//dp[i][j]: M[i]??????M[j]?????§??????????????????????°??????°
//dp[i][j] = min(dp[i][j], dp[i][k] + dp[k+1][j] + prod)
//k = [i, j)
//prod = M[i].row * M[k].col * M[j].col

void solve() {
  cin >> n;
  rep(i,0,n)
  {
    cin >> M[i].first >> M[i].second;
    dp[i][i] = 0;
  }
  for (int i = 0; i + 1 < n; ++i) {
    dp[i][i + 1] = M[i].first * M[i].second * M[i + 1].second;
    dbp4(i, M[i], M[i + 1], dp[i][i + 1]);
  }
  for (int num_matrix = 3; num_matrix <= n; ++num_matrix) { //number of matrix A*B*C -> 3
    for (int i = 0, j = i + num_matrix - 1; j < n; ++i, ++j) {
      dbp4(i, M[i], M[j], dp[i][j]);
      int mini = INT_MAX;
      for (int k = i; k + 1 <= j; ++k) {
        int prod = M[i].first * M[k].second * M[j].second;
        mini = min(mini, dp[i][k] + dp[k + 1][j] + prod);
      }
      dp[i][j] = mini;
      dbp4(i, M[i], M[j], dp[i][j]);dbp("----------");
    }
  }
  cout << dp[0][n - 1] << endl;
}

int main() {
  solve();
}

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

using namespace std;

int main () {

    int i, j, k, l, n, p[101], m[101][101];

    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++) {
            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;

}

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[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 p[105];
int m[110][110];
int n;

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> p[i - 1];
		cin >> p[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] = (i << 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] << "\n";
	return 0;
}