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;
using UL = unsigned int;
using ULL = unsigned long long;
using LL = long long;
#define rep(i,n) for(UL i=0; i<(n); i++)

UL N;
ULL dp[101][101];
ULL R[100][2];

int main() {
 cin>>N;
 rep(i,N) rep(j,2) cin>>R[i][j];
 rep(i,N+1) rep(j,N+1) dp[i][j]=1000000000000;
 rep(i,N) dp[i][i+1]=0;
 for(UL j=2; j<=N; j++) for(UL i=j-2; i!=~0u; i--){
  for(UL k=i+1; k<=j-1; k++){
   dp[i][j]=min(dp[i][j],
    dp[i][k]+dp[k][j]+R[i][0]*R[j-1][1]*R[k][0]
   );
  }
 }
 cout<<dp[0][N]<<endl;
 return 0;
}

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] * r[i + j - 1];
		}
	}
	printf("%d\n", dp[0][n]);
	return 0;
}

C++: #include <bits/stdc++.h>
#define REP(i, n) for(int i = 0;i < n;i++)
#define ll long long
using namespace std;
//typedef vector<unsigned int>vec;
//typedef vector<ll>vec;
//typedef vector<vec> mat;
typedef pair<int, int> P;
typedef pair<ll,ll> LP;
const int dx[8] = {1, 0, -1, 0, 1, -1, -1, 1};
const int dy[8] = {0, 1, 0, -1, 1, 1, -1, -1};
const int INF = 1000000000;
const ll LINF = 1000000000000000000;//1e18
const ll  MOD = 1000000007;
const double PI = acos(-1.0);
const double EPS = 1e-10;

template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
//template<class T> inline void add(T &a, T b){a = ((a+b) % MOD + MOD) % MOD;};

int dp[111][111];
int mat[111][2];

int solve(int l, int r){
    if(l + 1 >= r) return 0;
    if(dp[l][r]) return dp[l][r];

    int mi = INF;
    for(int i=l+1;i<r;++i){
        chmin(mi, solve(l, i) + solve(i, r) + mat[l][0] * mat[i][0] * mat[r-1][1]);
    }
    return dp[l][r] = mi;
}

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    REP(i,n) cin >> mat[i][0] >> mat[i][1];
    cout << solve(0,n) << endl;
}

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

#define MAX_N 100
#define R(i) (m[2*(i)])
#define C(i) (m[2*(i)+1])

typedef int int32_t;

// ??????????¨????????????§DP???

int main(void) {
    int n;
    int m[2 * MAX_N] = {};

    int dp[MAX_N][MAX_N] = {};

    scanf("%d", &n);
    for (int i = 0; i < n; i++) {
        scanf("%d %d", &R(i), &C(i));
    }

    for (int i = 0; i < n-1; i++) {
        dp[i][i + 1] = R(i) * C(i) * C(i+1);
    }
    for (int i = 2; i < n; i++) {
        for (int j = 0; j <= n - i; j++) {
            dp[j][i + j] = INT32_MAX;
            for (int k = 0; k < i; k++) {
                 dp[j][i + j] = min(dp[j][i + j], dp[j][j+k] + dp[j+k+1][i+j] + R(j) * R(j+k+1) * C(i+j));
            }
        }
    }

    printf("%d\n", dp[0][n-1]);
    return 0;
}

C++: #include <stdio.h>
#include <limits.h>
#define MAX 100

int main(){
	int n, m[MAX+1][MAX+1];
	int i, j, k, r, min;
	
	scanf("%d", &n);
	for(i=1;i<=n;++i) {
		scanf("%d %d", &m[i][i-1], &m[i+1][i]);
		m[i][i] = 0;
	}
	
	for(r=2;r<=n;++r){
		for(i=1;i<=n-r+1;++i){
			j=i+r-1;
			m[i][j] = INT_MAX;
			for(k=i;k<=j-1;++k){
				min = m[i][k]+m[k+1][j]+m[i][i-1]*m[k+1][k]*m[j+1][j];
				if(m[i][j] > min) m[i][j] = min;
			}
		}
	}
	printf("%d\n", m[1][n]);
	return 0;
}

C++: #include <iostream>
#include <vector>

using namespace std;

const int INFTY = (1<<30);

int main()
{
    int N;
    cin >> N;
    vector<int> A(N + 1);
    for (int i = 0; i < N; i++)
    {
        cin >> A[i] >> A[i + 1];
    }

    vector< vector<int> > cost(N);
    cost[0].assign(N, 0);
    for (int l = 2; l < N + 1; l++)
    {
        cost[l - 1].assign(N - l + 1, INFTY);
        for (int num = 0; num < N - l + 1; num++)
        {
            for (int k = 1; k < l; k++)
            {
                cost[l-1][num] = min(
                    cost[l-1][num],
                    cost[k-1][num] + cost[l-1-k][num+k] + A[num]*A[num+k]*A[num+l]
                );
            }
        }
    }
    cout << cost[N-1][0] << endl;
}

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

static const int N = 100;

int main()
{
  int p,ppp[N+1],m[N+1][N+1];

  cin >> p;

  for( int i = 1; i <= p; i++)
    {
      cin >> ppp[i-1] >> ppp[i];
    }

  for (int i = 1; i <= p; i++) m[i][i] = 0;
  for (int k = 2; k <= p; k++)
    {
      for(int i = 1; i <= p-k+1 ; i++)
	{
	  int j = i + k - 1;
	  m[i][j] = (1 << 21);

	  for ( int q = i; q <= j-1 ; q++)
	    {
	      m[i][j] = min(m[i][j], m[i][q] + m[q+1][j] +
			      ppp[i-1] * ppp[q] * ppp[j]);
	    }
	}
    }

  cout << m[1][p] << endl;

  return 0;
}