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<vector>
using namespace std;

void compute(vector<vector<int> > & cost,vector<vector<int> > & best,
			 vector<int> & A,int s,int e){
	int minc = 0;
	int mink = -1;
	for(int k=s+1;k<=e;++k){
		if (cost[s][k-1] < 0){
			compute(cost,best,A,s,k-1);
		}
		if (cost[k][e] < 0) {
			compute(cost,best,A,k,e);
		}
		int c = cost[s][k-1] + A[s]*A[k]*A[e+1] + cost[k][e];
		if (mink < 0 || c < minc) {
			minc = c;
			mink = k;
		}
	}
	cost[s][e] = minc;
	best[s][e] = mink;
}

int main(){
	vector<vector<int> > cost,best;
	vector<int> A;
	int n;
	cin >> n;
	A.resize(n+1);
	for(int i=0;i<n;++i) {
		int r,c;
		cin >> r >> c;
		if (i==0){
			A[0] = r;
		}
		if (A[i] != r){ cout << "error";exit(0);}
		A[i+1] = c;
	}
	cost.resize(n);
	best.resize(n);
	for(int i=0;i<n;++i){
		cost[i].resize(n);
		best[i].resize(n);
		for(unsigned j=0;j<cost[i].size();++j){
			cost[i][j] = -1;
			best[i][j] = -1;
		}
		cost[i][i]=0;
		best[i][i]=i;
	}
	compute(cost,best,A,0,n-1);
	cout << cost[0][n-1] << std::endl;
	return 0;
}

C++: #include <iostream>
#define INF 100001
 
using namespace std;
 
int main(){
  int n;
  cin >> n;
  int dp[n+1][n+1],p[n+1];
  cin >> p[0] >> p[1];
  for(int i=2;i<=n;i++){
    int t; cin >> t;
    cin >> 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]=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;
}

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

using namespace std;

const int MAX_N = 100;
const long long INF = 10000000000000;

long long DP[MAX_N][MAX_N];
pair<int,int> P[MAX_N];

int main()
{
	int n;
	long long q;
	cin >> n;
	for(int i=0;i<n;i++){
		scanf("%d",&P[i].first);
		scanf("%d",&P[i].second);
	}
	fill(DP[0],DP[n],INF);
	for(int i=0;i<n;i++){
		DP[i][i] = 0;
	}
	for(int l=1;l<n;l++){
		for(int i=0;i<n-l;i++){
			for(int k=i;k<i+l;k++){
				q = DP[i][k] + DP[k+1][i+l] + P[k].second * P[i].first * P[i+l].second;
				if(q < DP[i][i+l]){
					DP[i][i+l] = q;
				}
			}
		}
	}
	cout << DP[0][n-1] << "\n";
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <cstdio>
#include <cstdlib>
#include <string>
#include <iostream>
#include <climits>

using namespace std;

int main() {
	int i, j, k, to, min, temp_result;
	int n;
	int r[100], c[100];
	int result[100][100];
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> r[i] >> c[i];
		result[i][i] = 0;
	}
	
	i = 0;
	j = 1;
	to = n - 2;
	while (j <= n - 1) {
		while (i <= to) {
			//computation of result[i][i+j]
			min = INT_MAX;
			k = i;
			while (k <= i + j - 1) {
				temp_result = c[k] * r[i] * c[i + j] + result[i][k] + result[k + 1][i + j];
				if (temp_result < min) {
					min = temp_result;
				}
				k++;
			}
			result[i][i + j] = min;
			i++;
		}
		i = 0;
		j++;
		to--;
	}
	printf("%d\n", result[0][n - 1]);
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
#define N 100

int main()
{
	int n;
	cin >> n;
	int p[N + 1], m[N + 1][N + 1];
	for (int i = 0; i < n; i++) {
		cin >> p[i] >> p[i + 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; 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 <bits/stdc++.h>

using namespace std;
using ll =long long;

#define SORT(a) sort((a).begin(),(a).end())
#define rSORT(a) reverse((a).begin(),(a).end())
#define For(i, a, b)    for(int i = (a) ; i < (b) ; ++i)
#define rep(i, n)       For(i, 0, n)
#define debug(x)  cout << #x << " = " << (x) << endl;
void coY() {cout <<"Yes"<<endl;}
void coN(){cout <<"No"<<endl;}

template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
const ll INF = 1LL << 60;

//Write From this Line

static const int N = 100;
int main()
{
	int n, p[N+1], m[N+1][N+1];
	cin >> n;
	rep(i,n) cin >> p[i] >> p[i+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] = min(m[i][j], m[i][k] + m[k + 1][j] +p[i-1] * p[k] * p[j]);
			}
		}
	}
	cout << m[1][n] << endl;
}

C++: #include<iostream>
#include<stdio.h>
#include<stdlib.h>

using namespace std;



int main(){
  int n;
  cin>>n;
  int r[100];
  int m[101][101];
  int j;
  int q=0;
  //int c[n];
  for(int i=1;i<=n;i++){
    cin>>r[i]>>r[i-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++){
      j=i+l-1;
      m[i][j]=2000000000;
      for(int k=i;k<j;k++){
	q=m[i][k]+m[k+1][j]+r[i-1]*r[k]*r[j];
	m[i][j]=min(m[i][j],q);
      }
    }
  }
  
  cout<<m[1][n]<<endl;
  return 0;
}