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 "bits/stdc++.h"
using namespace std;
#ifdef _DEBUG
#include "dump.hpp"
#else
#define dump(...)
#endif

//#define int long long
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(c) begin(c),end(c)
const int INF = sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;
const int MOD = 1'000'000'007;
template<class T> bool chmax(T &a, const T &b) { if (a < b) { a = b; return true; } return false; }
template<class T> bool chmin(T &a, const T &b) { if (b < a) { a = b; return true; } return false; }

int R[101], C[101];
int dp[101][101];

int f(int l, int r) {
	dump(l, r);
	if (dp[l][r] != INF)return dp[l][r];
	if (l >= r - 1)return 0;
	rep(m, l + 1, r) {
		chmin(dp[l][r], f(l, m) + f(m, r) + R[l] * R[m] * C[r - 1]);
	}
	return dp[l][r];
}

signed main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	int n; cin >> n;
	rep(i, 0, n)cin >> R[i] >> C[i];
	memset(dp, 0x3f, sizeof(dp));
	cout << f(0, n) << endl;
	return 0;
}

C++: #include "bits/stdc++.h"
#include "math.h"
 
using namespace std;
typedef long long ll;
typedef vector<ll> vll;
typedef vector<vll> vvll;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<int> vin;
typedef pair<ll,ll> P;
typedef vector<P> vp;
#define rep(i,a,b) for(ll i=(a);i<(b);++i)
#define drep(i,a,b) for(ll i=(a);i>=(b);--i)
#define SIZE(a) int((a).size())
#define out(a) cout<<(a)<<endl;
const int INF=INT_MAX;
const int MAX = 510000;
const ll MOD = 1000000007;
ll fac[MAX], finv[MAX], inv[MAX];

int main(){
  ll n;cin>>n;
  vll p(n+1);
  vvll dp(n,vll(n,MOD));
  rep(i,0,n){
    cin>>p[i]>>p[i+1];
  }
  rep(i,0,n){
    dp[i][i]=0;
  }
  rep(haba,0,n){
    rep(i,0,n-haba){
      int j=i+haba;
      rep(k,i,j){
        dp[i][j]=min(dp[i][j],dp[i][k]+dp[k+1][j]+p[i]*p[k+1]*p[j+1]);
      }
    }
  }
  cout<<dp[0][n-1]<<endl;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <cmath>
#include <set>
#include <algorithm>
#include <array>
#include <complex>
#include <utility>
#include <map>
int needleX[4] = { -1,0,1,0 };
int needleY[4] = { 0,1,0,-1 };

int main(void) {
    int n;

    std::cin >> n;
    std::vector<int> p(100+1);
    for (int i = 1; i <= n; i++) {
        std::cin >> p[i-1] >> p[i];
    }
    int m[100 + 1][100 + 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] = (1<<21);
            for (int k = i ; k <= j - 1;k++) {
                m[i][j] = std::min(m[i][j],  m[i][k] + m[k + 1][j] + p[i - 1] * p[k] * p[j]);
            }
        }
    }
    /*for (int i = 1; i <= n; i++) {
        for (int j = i+1; j <= n; j++) {
            std::cout << m[i][j] << " ";
        }
        std::cout << std::endl;
    }*/
    std::cout << m[1][n] << std::endl;
    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

long long int n, mat[100+1][100+1], len[100+1];

int main(void){
  int i, j, k, l;

  scanf("%d", &n);
  
  for(int i=1; i<=n; i++){
    scanf("%d %d", &len[i-1], &len[i]);
  }
  
  for(l=2; l<=n; l++){
    for(i=1; i<=n-l+1; i++){
      j=i+l-1;
      mat[i][j]=INT_MAX;

      for(k=i; k<=j-1; k++){
	mat[i][j]=min(mat[i][j], mat[i][k]+mat[k+1][j]+len[i-1]*len[k]*len[j]);
      }
    }
  }

  printf("%d\n", mat[1][n]);
  
  return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <string>
#include <cctype>
#include <stack>
#include <queue>
#include <vector>
#include <cstdlib>
#include <list>
#define _USE_MATH_DEFINES
#include <math.h>

using namespace std;

int main() {

	int n, p[101], m[101][101];

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

	for (int i = 2; i <= n; i++) {
		for (int j = 1; j <= n - i; j++) {
			int k = i + j - 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;

	return 0;
}

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

#define N 100

int M[101][101], p[101], n;

int solve()
{
	int l, i, j, k;
	for (l = 2; l <= n; l++) {
		for (i = 1; i <= n - l + 1; i++) {
			j = i + l - 1;
			M[i][j] = INT32_MAX;
			for (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]);
		}
	}
	return M[1][n];
}

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

	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;

	cout << solve() << endl;
	return 0;
}