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;



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;
}

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

int main() 
{
	int n, m[101][101], p[101];
	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 j = 2; j <= n; j++) 
	{
		for (int i = 1; i <= n - j + 1; i++) 
		{
			int k = i + j - 1;
			m[i][k] = INT_MAX;
			for (int l = i; l <= k - 1; l++)
				m[i][k] = min(m[i][k], m[i][l] + m[l + 1][k] + p[i - 1] * p[l] * p[k]);
		}
	}

	cout << m[1][n] << endl;

	return 0;
}

C++: #include<stdio.h>
#include<algorithm>
using namespace std;

static const int N = 100;

int main(){
  int n, p[N + 1], m[N + 1][N + 1];
  cin >> n;l <= n; l++){
  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 - 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;
}

C++: // ?????¬???????????¬??????

#include <iostream>
#include <iomanip>
#include <cstdio>
#include <string>
#include <cstring>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <complex>
#include <cmath>
#include <limits>
#include <cfloat>
#include <climits>
#include <ctime>
#include <cassert>
#include <numeric>
#include <functional>
using namespace std;

#define rep(i,a,n) for(int (i)=(a); (i)<(n); (i)++)
#define repq(i,a,n) for(int (i)=(a); (i)<=(n); (i)++)
#define repr(i,a,n) for(int (i)=(a); (i)>=(n); (i)--)
#define int long long int

template<typename T> void chmax(T &a, T b) {a = max(a, b);}
template<typename T> void chmin(T &a, T b) {a = min(a, b);}
template<typename T> void chadd(T &a, T b) {a = a + b;}

typedef pair<int, int> pii;
typedef long long ll;

int dx[] = {0, 0, 1, -1};
int dy[] = {1, -1, 0, 0};
constexpr ll INF = 1001001001001001LL;
constexpr ll MOD = 1000000007LL;

int N;
int R[110], C[110];

// [i, j) ???????????????????????°????°?
int dp[110][110];

signed main() {
    cin >> N;
    rep(i,0,N) cin >> R[i] >> C[i];
    repq(i,0,N) {
        repq(j,0,N) {
            if(i < j && j-i != 1) {
                dp[i][j] = dp[i][j-1] + R[i] * R[j-1] * C[j-1];
                // printf("dp[%lld][%lld] = %lld\n", i, j, dp[i][j]);
            }
        }
    }

    repq(i,3,N) {
        rep(j,0,N-i+1) {
            rep(k,j+1,j+i-1) {
                chmin(dp[j][j+i], 
                      dp[j][k] + dp[k][j+i] + R[j] * R[k] * C[j+i-1]);
            }
        }
    }
    cout << dp[0][N] << endl;
    return 0;
}

C++: /*
 * b.cc: 
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>

using namespace std;

/* constant */

const int MAX_N = 100;
const int INF = 1 << 30;

/* typedef */

/* global variables */

int rs[MAX_N], cs[MAX_N];
int dp[MAX_N][MAX_N];

/* subroutines */

/* main */

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

  for (int i = 0; i < n; i++) cin >> rs[i] >> cs[i];

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

  int sum = 0;

  for (int l = 1; l < n; l++)
    for (int i0 = 0, i1 = l; i1 < n; i0++, i1++) {
      dp[i0][i1] = INF;
      for (int j = i0; j < i1; j++) {
	int d = rs[i0] * cs[j] * cs[i1] + dp[i0][j] + dp[j + 1][i1];
	if (dp[i0][i1] > d) dp[i0][i1] = d;
      }
    }

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

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

using namespace std;
#define N 100

int main(){
  int n;
  int M[N+1][N+1],p[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 i=2;i<=n;i++){
    for(int j=1;j<=n-i+1;j++){
      int k=j+i-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;
}