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<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 <cstdlib>
#include <climits>

/*
 * http://ttrsq.exblog.jp/24318687/
 */

const int MAX_N = 100;
int DP[MAX_N + 1][MAX_N + 1] = {0};
int *p;

int best(int r, int c) {
  int min = INT_MAX;
  int num = c - r;

  for (int i = 0; i < num; i++) {
    min = std::min(min, DP[r][r + i] + DP[r + i + 1][c] + p[r - 1] * p[r + i] * p[c]);
  }
  
  return min;
}

int main() {
  std::cin.tie(0);
  std::ios::sync_with_stdio(false);

  int n = 0;
  std::cin >> n;

  if (n == 1) {
    std::cout << "0" << std::endl;
  }
  
  p = (int *) std::malloc(sizeof(int) * n + 1);

  int bb = 0;

  std::cin >> p[0];
  std::cin >> p[1];
  
  for (int i = 2; i <= n; i++) {
    std::cin >> bb;
    std::cin >> p[i];
  }

  for (int i = 1; i < n; i++) {
    DP[i][i + 1] = p[i - 1] * p[i] * p[i + 1];
  }

  for (int j = 0; j <= n - 3; j++) {
    for (int i = j + 3; i <= n; i++) {
      DP[i - 2 - j][i] = best(i - 2 - j, i);
    }
  }

  std::cout << DP[1][n] << std::endl;

  return 0;
}

C++: #include <algorithm>
#include <bitset>
#include <cassert>
#include <cmath>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <string>
#include <vector>

// Acknowledgement: Special thanks to kyomukyomupurin, who developed this
// template.
template <class T, class U>
std::ostream& operator<<(std::ostream& os, const std::pair<T, U>& p) {
  return os << '(' << p.first << ", " << p.second << ')';
}

template <class T>
std::ostream& operator<<(std::ostream& os, const std::vector<T>& vec) {
  int n = 0;
  for (auto e : vec) os << (n++ ? ", " : "{") << e;
  return os << (n ? "}" : "{}");
}

template <class T>
std::ostream& operator<<(std::ostream& os, const std::set<T>& st) {
  int n = 0;
  for (auto e : st) os << (n++ ? ", " : "{") << e;
  return os << (n ? "}" : "{}");
}

template <class T, class U>
std::ostream& operator<<(std::ostream& os, const std::map<T, U>& mp) {
  int n = 0;
  for (auto e : mp) os << (n++ ? ", " : "{") << e;
  return os << (n ? "}" : "{}");
}

template <class T>
std::istream& operator>>(std::istream& is, std::vector<T>& vec) {
  for (T& e : vec) is >> e;
  return is;
}

#ifdef LOCAL
#define debug(...) \
  std::cerr << "[" << #__VA_ARGS__ << "]: ", debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif

void debug_out() { std::cerr << '\n'; }

template <class Head, class... Tail>
void debug_out(Head&& head, Tail&&... tail) {
  std::cerr << head;
  if (sizeof...(Tail) != 0) std::cerr << ", ";
  debug_out(std::forward<Tail>(tail)...);
}
using namespace std;
using int64 = long long;

int main() {
  int n;
  cin >> n;
  vector<int> p(n + 1);
  for (int i = 0; i < n; i++) {
    cin >> p[i] >> p[i + 1];
  }
  vector<vector<int>> dp(n + 1, vector<int>(n + 1));
  for (int l = 2; l <= n; l++) {
    for (int i = 1; i <= n - l + 1; i++) {
      int j = i + l - 1;
      if (i == j)
        dp[i][j] = 0;
      else {
        int tmp = 1e9;
        for (int k = i; k < j; k++) {
          tmp = min(tmp, dp[i][k] + dp[k + 1][j] + p[i - 1] * p[k] * p[j]);
        }
        dp[i][j] = tmp;
      }
    }
  }
  debug(dp);
  cout << dp[1][n] << endl;
  return 0;
}

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

const int INF = 1 << 28;

int main()
{
    int n;
    int dp[101][101];
    int r[102];
    
    cin >> n;
    
    fill((int*)dp, (int*)(dp + n), INF);
    
    for(int i = 0; i < n; ++i){
        cin >> r[i] >> r[i + 1];
        dp[i][i] = 0;
    }
    
    for(int w = 1; w < n; ++w){
        for(int i = 0, j ; j = i + w, j < n; ++i){
            for(int k = i; k < j; ++k){
                dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j] + r[i] * r[k + 1] * r[j + 1]);
            }
        }
    }
    
    cout << dp[0][n-1] << endl;
    
}

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

void MatrixChainMultiplication(int n,int p[],int m[101][101]) {
	int i, j, k,l;
	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]);
			}
		}
	}
}

int main() {
	int n, p[101], m[101][101];
	cin >> n;
	for (int i = 1; i <= n; i++) cin >> p[i - 1] >> p[i];
	MatrixChainMultiplication(n, p, m);
	cout << m[1][n] << endl;

	
}