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 <cmath>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <climits>
#include <map>
#include <list>
#include <stack>
#include <queue>
#include <vector>
#include <string>
#include <sstream>
#include <fstream>
#include <iostream>
#include <algorithm>
using namespace std;

int m[128], costs[128][128];
int calc(int s, int e){
	if(s==e) return 0;
	if(costs[s][e] == INT_MAX){
		if(e-s==1) return costs[s][e] = m[s-1] * m[s] * m[e];
		for(int i = s; i < e; i++){
			costs[s][e] = min(costs[s][e], calc(s, i) + calc(i+1, e) + m[s-1] * m[i] * m[e]);
		}
	}
	return costs[s][e];
}

int main() {
	int n;
	scanf("%d", &n);
	
	for(int i = 0; i < n; i++){
		scanf("%d %d", &m[i], &m[i+1]);
	}
	
	for(int i = 0; i <= n; i++){
		for(int j = 0; j <= n; j++){
			costs[i][j] = INT_MAX;
		}
	}
	
	printf("%d\n", calc(1, n));
	
	return 0;
}

C++: #include <bits/stdc++.h>
#define r(i,n) for(int i=0;i<n;i++)
using namespace std;
int dp[111][111],n,L[111],R[111];
int dfs(int l,int r){
	if(dp[l][r]>-1)return dp[l][r];
	int res=1e9;
	for(int i=l;i<r;i++){
		res=min(res,dfs(l,i)+dfs(i+1,r)+L[l]*R[i]*R[r]);
	}
	return dp[l][r]=res;
}
main(){
	memset(dp,-1,sizeof(dp));
	r(i,111)dp[i][i]=0;
	cin>>n;
	r(i,n)cin>>L[i]>>R[i];
	cout<<dfs(0,n-1)<<endl;
}

C++: #include <cstdio>

struct Matrix
{
  int row;
  int column;
  int multiple_time;

  Matrix():
    row(0), column(0), multiple_time(0)
  {}

  Matrix(int r, int c, int m):
    row(r), column(c), multiple_time(m)
  {}
};

Matrix multiple(Matrix mat1, Matrix mat2)
{
  return Matrix(mat1.row,
                mat2.column,
                mat1.multiple_time + mat2.multiple_time + mat1.row * mat1.column * mat2.column);
}

Matrix matrices[100];
Matrix multiplication[100][100];

Matrix minimum_multiple_time(int i, int j)
{
  if (i == j)
    return matrices[i];

  Matrix min = multiple(multiplication[i][i], multiplication[i + 1][j]);

  for (int k = 1; k < j - i; ++k)
  {
    Matrix cur_matrix = multiple(multiplication[i][i + k], multiplication[i + k + 1][j]);
    if (min.multiple_time > cur_matrix.multiple_time)
      min = cur_matrix;
  }

  return min;
}

int main()
{
  int n;
  scanf("%d", &n);

  for (int i = 0; i < n; ++i)
    scanf("%d%d", &matrices[i].row, &matrices[i].column);

  for (int i = 0; i < n; ++i)
  {
    for (int j = 0; i + j < n; ++j)
    {
      multiplication[j][i + j] = minimum_multiple_time(j, i + j);
    }
  }

  printf("%d\n", multiplication[0][n - 1].multiple_time);

  return 0;
}

C++: #include<cstdio>
#include <cstring>
using namespace std;

int r[105];
int c[105];
int cache[105][105];

int f(int a, int b) {
    if (a == b) return 0;
    if (cache[a][b] == -1) {
        cache[a][b] = 2000000000;
        for (int i = a; i < b; i++) {
            int res = f(a, i) + f(i + 1, b) + r[a] * c[i] * c[b];
            if (res < cache[a][b]) cache[a][b] = res;
        }
    }
    return cache[a][b];
}

int main(void) {
    int n;
    scanf("%d",&n);
    for (int i = 0; i < n; i++) scanf("%d %d",&r[i], &c[i]);
    memset(cache, -1, sizeof(cache));
    printf("%d\n",f(0,n-1));
}

C++: #include<iostream>
using namespace std;
int dp[101][101];
class point {
public: int x, y;
};
point p[101];
int n;
int solve(int left, int right) {
	if (left == right) return dp[left][right] = 0;
	if (dp[left][right]) return dp[left][right];
	else
	{
		int min = 1<<29;
		for (int i = left; i < right; i++) {
			int k = dp[left][i] + dp[i + 1][right] + p[left].x * p[i + 1].x * p[right].y;
			if (k < min) min = k;
		}
		 dp[left][right] = min;
		 return min;
	}
}
int main(void) {
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> p[i].x>>p[i].y;
	}
	for(int l=1;l<n; l++)
	for (int i = 0; i < n; i++) {
		if (i + l < n)
		{
			solve(i, i + l);
		}
	}
	cout << dp[0][n - 1]<<endl;
}

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

#define int long long
 
#define rep(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)

#define YES puts("YES")
#define Yes puts("Yes")
#define NO  puts("NO")
#define No  puts("No")
#define ALL(v) (v).begin(), (v).end()
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

//*
#define mod 1000000007 /*/
#define mod 998244353 //*/

typedef pair<int, int> P;
#define INF (1LL<<60)



void solve(){
    int N;
    cin >> N;
    vector<int> p(N+1,0);
    for(int i=0; i<N; i++)
        cin >> p[i] >> p[i+1];
    
    vector<vector<int>> dp(N+1, vector<int>(N+1,0));
    
    for(int w=2; w<=N; w++){
        for(int i=1; i<=N-w+1; i++){
            int j=i+w-1;
            dp[i][j] = INF;
            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;
}


signed main(){
    cout << fixed << setprecision(18);
    cerr << fixed << setprecision(18);
    solve();
}