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 <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
 
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
 
using namespace std;
 
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
 
const int INF=1<<29;
const double EPS=1e-9;
 
const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};

int dp[100][100] = {{0}};
std::vector<int> r;
std::vector<int> c;
int N;

int dfs(int i, int j) {
	if (dp[i][j] != 0) {return dp[i][j];}
	if (j == i) {
		return 0;
	}
	if (j - i == 1) {
		return dp[i][j] = r[i] * c[i] * c[j];
	}
	int ans = 1000000000;
	for (int k = i; k < j; ++k) {
		ans = std::min(ans, dfs(i, k) + dfs(k + 1, j) + r[i] * c[k] * c[j]);
	}
	return dp[i][j] = ans;
}

int main(int argc, char const *argv[]) {
	cin >> N;
	for (int i = 0; i < N; ++i) {
		int a, b;
		cin >> a >> b;
		r.push_back(a);
		c.push_back(b);
	}
	int ans = dfs(0, N - 1);
	cout << ans << endl;

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define REP(i,n) for(int i=0; i<(n); i++)
#define REP2(i,x,n) for(int i=x; i<(n); i++)
#define PRINT(x) cout<<(x)<<endl
#define INF 1000000000000 // 10^12
#define MOD 1000000007 // 10^9+7
#define PB push_back
#define MP make_pair

const int MAX_N = 100;

int n;
int r[MAX_N], c[MAX_N];

int dp[MAX_N][MAX_N];

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

    REP(i, n) {
        REP(j, n) dp[i][j] = MOD;
    }

    REP(i, n) dp[i][i] = 0;

    REP2(k, 1, n) {
        REP(i, n - k) {
            int j = i + k;
            REP2(l, i, j) {
                dp[i][j] = min(dp[i][j], dp[i][l] + dp[l+1][j] + r[i]*c[l]*c[j]);
            }
        }
    }

    PRINT(dp[0][n-1]);
    return 0;
}

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

const ll INF = 1e+18 + 10;
const int MAX_N = 100;
ll dp[MAX_N][MAX_N];

int main()
{
    int n;
    cin >> n;
    vector<int> r;

    for (int i = 0; i < n; i++)
    {
        int row, col;
        cin >> row >> col;
        if (i == 0)
        {
            r.push_back(row);
        }
        r.push_back(col);
    }

    // DPの初期化
    for (int i = 0; i < n; i++)
    {
        for (int j = 0; j < n; j++)
        {
            if (i == j)
            {
                dp[i][i] = 0;
            }
            else
            {
                dp[i][j] = INF;
            }
        }
    }

    // DPの更新
    for (int j = 1; j < n; j++)
    {
        for (int i = 0; i + j < n; i++)
        {
            for (int k = 0; k <= i + j; k++)
            {
                ll prod = r[i] * r[k + 1] * r[i + j + 1];
                dp[i][i + j] = min(dp[i][i + j], dp[i][k] + dp[k + 1][i + j] + prod);
            }
        }
    }

    cout << dp[0][n - 1] << endl;
    return 0;
}

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

int main(){
	int n, p[101],m[101][101];
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>p[i-1]>>p[i]
		}
		
	for(int i=1 ; i<=101 ; 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[l][n]<<endl;
	return 0;
	
}

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

#define MAX_N 10000
#define INF 10000000LL

long long n, j, x[MAX_N][MAX_N], p[MAX_N + 2], sum;

int matrix() {
	for (int i = 0; i < n; i++) { x[i][i] = 0; }
	for (int h = 2; h <= n; h++) {
		for (int i = 1; i <= n - h + 1; i++) {
			j = i + h - 1;
			x[i][j] = INF;
			for (int k = i; k < j; k++) {
				x[i][j] = min(x[i][j], x[i][k] + x[k + 1][j] + p[i - 1] * p[k] * p[j]);
			}
		}
	}
	sum = x[1][n];
	return sum;
}

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		cin >> p[i - 1] >> p[i];
	}
	cout << matrix() << endl;
	return 0;
}

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