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;
typedef long long ll;
const ll INF = 1e18;
const int inf = 1e9;
double pi = 3.14159265359;
#define rep(i, a, b) for (int i = a; i < b; i++)
#define per(i, b, a) for (int i = a - 1; i >= b; i--)
using Graph = vector<vector<int>>;
using pint = pair<int, int>;
int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
int dxx[8] = {1, 1, 1, 0, 0, -1, -1, -1}, dyy[8] = {-1, 0, 1, -1, 1, -1, 0, 1};

int main() {
    int n;
    cin >> n;
    int p[n + 1];
    rep (i, 1, n + 1) cin >> p[i - 1] >> p[i];
    int dp[n + 1][n + 1]; // i->jまでの計算をする時の最小回数
    rep (i, 0, n + 1) dp[i][i] = 0;
    rep (i, 2, n + 1) {
        rep (j, 1, n - i + 2) {
            int k = i + j - 1;
            dp[j][k] = inf;
            rep (l, j, k) {
                dp[j][k] = min (dp[j][k], dp[j][l] + dp[l + 1][k] +
                                              p[j - 1] * p[l] * p[k]);
            }
        }
    }
    cout << dp[1][n] << "\n";
}

C++: #include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
#include <utility>
#include <cmath>
#include <vector>
#include <queue>
#include <set>
#include <map>
#define rep(i, n) for(int i = 0; i < n; i++)
using namespace std;
typedef long long ll;
const ll mod = 1000000007;
const int INF = 1e9;

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

    int p[n+1];  // M_iはp[i]行p[i+1]列
    rep(i, n-1) {
        int ri, ci;
        cin >> ri >> ci;
        p[i] = ri; 
    }
    int rn, cn;
    cin >> rn >> cn;
    p[n-1] = rn, p[n] = cn;

    int dp[n][n];  // dp[i][j] : M_i・M_(i+1)・・・M_jの計算回数の最小値(i, jは0-index)
    rep(i, n) {
        rep(j, n) {
            if(i == j) {
                dp[i][j] = 0;
            }
            else {
                dp[i][j] = INF;
            }
        }
    }

    rep(j, n) {
        for(int i = n-1; i >= 0; i--) {
            if(j < i) {
                continue;
            }
            for(int k = i; k < j; k++) {
                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;
    return 0;
}

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

static const int N = 100;

int main(){
  int i, j, k, l, n, p[N + 1], m[N + 1][N + 1];
  cin >> n;

  for(i = 0 ; 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[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>

#define NIL -1
#define INF 1000000001

using namespace std;

void minChainMultiple(vector<vector<int> > &minMultipleArray,const vector<int> &matSizeArray){
    int n = (int) minMultipleArray.size();
    for(int l = 1;l < n;l++){
        for(int i = 0;i < n-l;i++){
            int j = i+l;
            minMultipleArray[i][j] = INF;
            for(int k = i;k < j;k++){
                minMultipleArray[i][j] = min(minMultipleArray[i][j],
                minMultipleArray[i][k] + minMultipleArray[k+1][j]+matSizeArray[i]*matSizeArray[k+1]*matSizeArray[j+1]);
            } 
        }
    }
    
}

int main(){
    int n;
    int row,column;
    scanf("%d",&n);
    vector<int> matSizeArray(n+1,0);
    vector<vector<int> > minMultipleArray(n,vector<int>(n,0)); 

    for(int i = 0; i < n;i++){
        scanf("%d %d",&row,&column);
        matSizeArray[i] = row;
        matSizeArray[i+1] = column;
    }
    minChainMultiple(minMultipleArray,matSizeArray);
    printf("%d\n",minMultipleArray[0][n-1]);
    return 0;
}

C++: 
#include<bits/stdc++.h>

using namespace std;

const int maxn=1e2+5;

int p[maxn],dp[maxn][maxn],n;

int main()
{
    scanf("%d",&n);
    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]=(1<<21);
            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;
}
/*
6
30 35
35 15
15 5
5 10
10 20
20 25
*/