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;

int dp[101][101];
int INF = 1000100100;


int main(){
    int n,r[101],c[101];
    cin >> n;
    for(int i=1; i<n+1; i++){
        cin >>r[i] >> c[i];
    }

    //dp[][]を初期化
    for(int i=0;i<101;i++){
        for(int j=0;j<101;j++){
            dp[i][j]=INF;
        }
    }

    //dp[i][i]=0にする。
    for(int i=1;i<n+1;i++){
        dp[i][i]=0;
    }
    //区間幅をずらしていく。2からスタート
    for(int k=2; k < n+1; k++){
        //対象区間の始点を一つずつ見ていく
        for(int i=1; i+k -1 < n+1; i++){
            //対象区間を2つの小区間にわける
            for(int j =i; j < i+k; j++){
                dp[i][i+k-1]=min(dp[i][i+k-1], dp[i][j]+dp[j+1][i+k-1] + r[i]*c[j]*c[i+k-1]);
            }
        }//添え字が間違ってないか不安。。
    }
    //全区間の答えを出力
    cout << dp[1][n] << endl;
    return 0;
}

C++: #include <iostream>
#include <sstream>
#include <cstdio>
#include <cmath>
#include <cctype>
#include <string>
#include <vector>
#include <list>
#include <set>
#include <map>
#include <queue>
#include <stack>
#include <algorithm>
#include <functional>

using namespace std;
using ll = long long int;
#define rep(i,n) for(int i = 0; i < n; i++)
#define FOR(i, a, b)  for(int i = (a); i < (b) ; i++)

#define pb push_back
#define SORT(v,n) sort(v, v+n)
#define ALL(x) (x).begin(),(x).end()
#define debug(x) cerr << #x << ": " << x << '\n'
#define elif else if
#define itn ll
#define int ll
const int INF = 100100100;
const int MOD = (int)1e9 + 7;
const double EPS = 1e-9;
///                →,↑,←,↓,↗,↖,↙,↘
int dx[8] = { 1, 0, -1, 0, 1, -1, -1, 1 };
int dy[8] = { 0, 1, 0, -1, 1, 1, -1, -1 };

static const int N = 100;

signed main() {
	ios::sync_with_stdio(false);
	int n, p[N + 1], m[N + 1][N + 1];
	cin >> n;
	int i;
	FOR(i, 1, n + 1) {
		cin >> p[i - 1] >> p[i];
	}
	FOR(i, 1, n + 1) 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] << '\n';
	return 0;
}

C++: #include <stdio.h>

int main() {	
	int rankN;
	int colRowL[101];
	int min[100][100];
	int left, right;
	int temp;
	int i, j, k;

	scanf("%d", &rankN);
	for (i = 0; i < rankN; i++) {
		scanf("%d %d", &colRowL[i], &colRowL[i + 1]);
	}

	for (i = 0; i < rankN; i++) {
		min[i][i] = 0;
	}
	for (i = 1; i < rankN; i++) {
		for (j = 0; j < rankN - i; j++) {
			left = j;
			right = j + i;
			min[left][right] = 1000000000;

			for (k = left; k < right ; k++) {
				temp = min[left][k] + min[k + 1][right] 
		                    +colRowL[left] * colRowL[k + 1] * colRowL[right + 1];
				if (temp < min[left][right]) {
					min[left][right] = temp;
				}
			}
		}
	}

	printf("%d\n", min[0][rankN - 1]);

	return 0;
}

C++: #include<iostream>
#include<cstdio>
#define INT_MAX 100000000
using namespace std;
int index;
int mm[1000][1000];
int mine = INT_MAX;

void solve(int p[]){
  int n = index-1,j,q;
  for(int i=1;i<=n;i++)mm[i][i]=0;
  for(int l=2;l<=n;l++){
    for(int i=1;i<=n-l+1;i++){
      j = i+l-1;
      mm[i][j] = INT_MAX;
      for(int k=i;k<=j-1;k++){
	q = mm[i][k] + mm[k+1][j] + p[i-1]*p[k]*p[j];
	if(q<mm[i][j]){
	  mm[i][j] = q;
       
	}

      }
    }
  }




}

int main(){
  int p[1000],a,b;
  scanf("%d",&index);
  //for(int i=0;i<=index;i++)for(int j=0;j<=n;j++)mm[i][j] = INT_MAX;
  for(int i=0;i<index;i++){
    scanf("%d %d",&a,&b);
    p[i] = a;
    if(i == index-1)p[i+1] = b;
  }

  index = index+1;
  solve(p);
 
  printf("%d\n",mm[1][index]);
  return 0;
}

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

int main() {
    int max = 100;
    int n;
    cin >> n; // take the input
    int p[max + 1], m[max + 1][max + 1];
    for (int i = 1; i <= n; i++) {
        cin >> p[i - 1] >> p[i]; // scan in the matrix
    }

    for (int i = 1; i <= n; i++) {
        m[i][i] = 0;
        for (int t = 2; t <= n; t++) {
            for (int i = 1; i <= n - t + 1; i++) {
                int j = i + t - 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;
}