Go: package main

import (
	"bufio"
	"fmt"
	"io"
	"math"
	"os"
	"strconv"
)

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	fmt.Println(resolve(parseProblem()))
}

type matrixSize struct{ row, col int }

func calcNum(i, j matrixSize) int {
	return i.row * j.col * i.col
}

func parseProblem() (int, []matrixSize) {
	n := scanInt(sc)
	sizes := make([]matrixSize, n)
	for i := 0; i < n; i++ {
		sizes[i] = matrixSize{row: scanInt(sc), col: scanInt(sc)}
	}
	return n, sizes
}

var dp [][]int

func initDP(n int) {
	dp = make([][]int, n+1)
	for i := 0; i < len(dp); i++ {
		dp[i] = make([]int, n+1)
		for j := 0; j < len(dp[i]); j++ {
			dp[i][j] = math.MaxInt64
		}
	}
}

func resolve(n int, sizes []matrixSize) int {
	// TODO 復習
	initDP(n)
	_rec(sizes, 0, n)
	return dp[0][n]
}

func _rec(sizes []matrixSize, l, r int) int {
	if dp[l][r] != math.MaxInt64 {
		return dp[l][r]
	}
	if r-l <= 1 {
		dp[l][r] = 0
		return 0
	}
	num := math.MaxInt64
	for i := l + 1; i < r; i++ {
		v := _rec(sizes, l, i) + _rec(sizes, i, r) + calcNum(matrixSize{sizes[l].row, sizes[i].row}, matrixSize{sizes[i].row, sizes[r-1].col})
		if v < num {
			num = v
		}
	}
	dp[l][r] = num
	return dp[l][r]
}

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

C++: //Matrix Chain Multiplication
#include <iostream>
#include <climits>

using namespace std;

int matrixChainMultiplication(int p[], int n) {
    int dp[n+1][n+1];
    for(int i = 0; i < n + 1; i++) dp[i][i] = 0;
    for(int l=2; l<n+1; l++) {
        for(int i=1; i<n-l+2; i++) {
            int j = i+l-1;
            dp[i][j] = INT_MAX;
            for(int k=i+1; k<j+1; k++) {
                dp[i][j] = min(dp[i][j], dp[i][k-1] + dp[k][j] + p[i - 1] * p[k - 1] * p[j]);
            }
        }
    }
    return dp[1][n];
}

int main() {
    int n, r, c;
    cin >> n;
    int p[n+1];
    for(int i=0; i<n; i++) {
        cin >> r >>  c;
        if(i == 0) p[0] = r;
        p[i+1] = c;
    }

    cout << matrixChainMultiplication(p, n) << endl;
}

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

using namespace std;

static const int N=100;

int main(){
int n,A[N+1],B[N+1][N+1];
cin>>n;
for(int i=1;i<=n;i++){
    cin>>A[i-1]>>A[i];
}
for(int i=1;i<=n;i++)B[i][i]=0;
for(int l=2;l<=n;l++){
    for(int i=1;i<=n-l+1;i++){
        int j=i+l-1;
        B[i][j]=(1<<21);
        for(int k=i;k<=j-1;k++){
            B[i][j]=min(B[i][j],B[i][k]+B[k+1][j]+A[i-1]*A[k]*A[j]);
        }
    }
}
cout<<B[1][n]<<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 = 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 - 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 <stdio.h>
#define N 101
#define INF 100000

int m[N][N];
int p[N];

int main(){
  int n, i, j, k, l, q;
  int trash;


  scanf("%d", &n);
  for ( i = 0; i < n; i++ ){
    scanf("%d%d", &p[i] ,&trash );
  }
  p[i] = trash;

  for( l = 2 ; l <= n ; l++ ){
    for( i = 1 ; i < (n+l-1) ; i++){
      j = i + l - 1;
      m[i][j] = INF;
      for( k = i ; k <= (j-1) ; k++ ){
	q = m[i][k] + m[k+1][j] + p[i-1]*p[k]*p[j];
	if( m[i][j] == -1 || m[i][j] > q){
	  m[i][j] = q;
	}
      }
    }
  }

  printf("%d\n" ,m[1][n]);

  return 0; // Don't forget 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;
}

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

int N ;
int a[101][101];
int m[101][2];

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

    for (int j = 1; j <= N; ++j) {
        a[j][j] = 0;
    }

    for (int k = 1; k < N; ++k) {
        for (int l = 1; l <= N- k ; ++l) {
            int j = l + k;
            int mn = INT_MAX;
            for (int p = l; p <= j-1 ; ++p) {
                mn = min(mn, a[l][p] + a[p+1][j] + m[l][0] * m[p][1] * m[j][1]);
            }
            a[l][j] = mn;
        }
    }
    cout << a[1][N] << endl;

    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n)   for(int i=0;i<(n);++i)
#define SORT(c)    sort((c).begin(),(c).end())
#define CLR(a)     memset((&a), 0 ,sizeof(a))//clear memory
#define dump(x)    cerr << #x << " = " << (x) << endl;//debug
#define debug(x)   cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;
#define EPS        1e-10//sample:if((double)>=(double)+EPS)
//cin,cout release
//std::cin.tie(0);
//ios::sync_with_stdio(false);
int m[101][101];
int p[101];
int l=0,n;
void matrixchainorder(){

  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]=INT_MAX;
      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]);
      }
    }
  }
}


int main(){

  int temp;
  cin>>n;
  rep(i,n+1)rep(j,n+1)m[i][j]=INT_MAX;
  for(int i=1;i<=n;i++)cin>>p[i-1]>>temp;
  p[n]=temp;
  matrixchainorder();
  cout<<m[1][n]<<endl;
  return 0;
}