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>
#include<vector>
#include<string>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<math.h>
using namespace std;
#define N (1000000000+7)
#define INF 1e16
typedef long long ll;
typedef pair<int,int> P;


ll dp[110][110];
bool flag[110][110];
int n;
vector<ll>p;

ll rec(ll left,ll right){
    if(flag[left][right])return dp[left][right];
    if(left == right){
        flag[left][right]=true;
        return dp[left][right]=0;
    }
    if(left>right){
        return 0;
    }
    if(right -left ==1){
        flag[left][right]=true;
        return dp[left][right] = p[left]*p[left+1]*p[left+2];
    }
    ll Min = INF;
    for(ll l=left;l<right;l++){
        Min =min(Min,rec(left,l)+rec(l+1,right)+p[left]*p[l+1]*p[right+1]);
    }
    flag[left][right]=true;
    return dp[left][right]=Min;
}

int main(void){
    cin>>n;
    vector<int>r(n),c(n);
    for(int i=0;i<n;i++)cin>>r[i]>>c[i];
    p.resize(n+2);
    p[1]=r[0];
    for(int i=2;i<=n+1;i++)p[i]=(c[i-2]);
    //dp[l][r]をl,l+1,...,r-1と定める
    cout<<rec(1,n)<<endl;
    
    return 0;
}

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<bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i=0; i<n; i++)
#define REP(i, n) for(int i=0; i<=n; i++)
#define repr(i, n) for(int i=n; i>0; i--)
#define REPR(i, n) for(int i=n; i>=0; i--)
#define FOR(i, a, b) for(int i=a; i<b; i++)
#define ALL(v) v.begin(),v.end()
#define pb push_back
#define eb emplace_back
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<int, ll> pil;
typedef pair<ll, int> pli;
typedef pair<ll, ll> pll;
const int INF = 1e9;
const ll LLINF = 1e18;
const ll MOD = 1e9+7;
template<class T> void puts(T x) { std::cout << x << std::endl; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

int n, r[105], c[105];
int dp[105][105];


int main() {
    cin >> n;
    rep(i, n) cin >> r[i] >> c[i];

    rep(i, n) rep(j, n) dp[i][j] = i == j ? 0 : INF;

    for (int i = 1; i < n; i++) {
        for (int j = i-1; j >= 0; j--) {
            for (int k = 0; k < i; k++) {
                int cost = dp[i][k+1] + dp[k][j] + r[j]*c[k]*c[i];
                chmin(dp[i][j], cost);
            }
        }
    }
    cout << dp[n-1][0] << endl;
}

C++: #include <stdio.h>
#include <algorithm>
using namespace std;
int n, r[100], c[100], dp[100][101];
int main() {
	scanf("%d", &n);
	for(int i = 0; i < n; i++) scanf("%d%d", &r[i], &c[i]), dp[i][i] = 0;
	for(int i = 1; i <= n; i++) {
		for(int j = 0; i + j <= n; j++) {
			dp[j][i + j] = min(dp[j][i + j - 1], dp[j + 1][i + j]) + c[j] * c[i + j - 1];
		}
	}
	printf("%d\n", dp[0][n]);
	return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <math.h>
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <map>
#include <set>
#include <queue>
#include <list>
#define rep(i,n) for(int i=0;i<(n);i++)
#define REP(i,a,b) for(int i=int(a);i<int(b);++i)
#define crep(i) for(char i='a';i<='z';i++)
#define psortsecond(A,N) sort(A,A+N,[](const pii &a, const pii &b){return a.second<b.second;});
#define psortfirst(A,N) sort(A,A+N,[](const pii &a, const pii &b){return a.first<b.first;});
#define All(x) (x).begin(),(x).end()
int ctoi(const char c){
  if('0' <= c && c <= '9') return (c-'0');
  return -1;
}
using namespace std;
using pii  = pair<int,int>;
long long gcd(long long a, long long b){return (b == 0 ? a : gcd(b, a%b));}
long long lcm(long long a, long long b){return a*b/gcd(a,b);}
typedef long long ll;
#define MOD 1000000007
#define EPS 10e-8

static const int N = 100;

int main(){
    ll N,P[107],m[107][107];
    cin >> N;
    REP(i,1,N+1){
        cin >> P[i-1] >> P[i];
    }
    REP(i,1,N+1){
        m[i][i]=0;
    }
    REP(l,2,N+1){
        REP(i,1,N-l+2){
            int j=i+l-1;
            m[i][j]=MOD;
            REP(k,i,j+1){
                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;
}