Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 500001), 500000)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func main() {
	fp := os.Stdin
	if len(os.Args) > 1 {
		fp, _ = os.Open(os.Args[1])
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(os.Stdout)

	n := getNextInt(scanner)
	mm := make([]int, n+1)
	dp := make([][]int, n+1)
	for i := 0; i <= n; i++ {
		dp[i] = make([]int, n+1)
	}
	for i := 0; i < n; i++ {
		mm[i] = getNextInt(scanner)
		mm[i+1] = getNextInt(scanner)
	}

	for l := 2; l <= n; l++ {
		for i := 1; i <= n-l+1; i++ {
			j := i + l - 1
			for k := i; k <= j-1; k++ {
				d := dp[i][k] + dp[k+1][j] + mm[i-1]*mm[k]*mm[j]
				if dp[i][j] == 0 || dp[i][j] > d {
					dp[i][j] = d
				}
			}
		}
	}

	fmt.Fprintln(writer, dp[1][n])

	writer.Flush()
}

C++: #include <iostream>
#include <vector>
#include <utility>
#include <map>
//#include "../cxx-prettyprint/prettyprint.hpp"
using std::vector;
using std::pair;

std::map<vector<pair<int, int>>, int> memo;

int get_minimum_multiplication(vector<pair<int, int>> matrix_sizes) {
    if (matrix_sizes.size() == 1) {
        return 0;
    } else if (matrix_sizes.size() == 2) {
        return matrix_sizes[0].first * matrix_sizes[0].second * matrix_sizes[1].second;
    } else if (memo.find(matrix_sizes) != memo.end()) {
        return memo[matrix_sizes];
    } else {
        int min_count = 0;
        for (int i = 1; i < matrix_sizes.size(); i ++) {
            vector<pair<int, int>> left, right;
            std::copy(matrix_sizes.begin(), matrix_sizes.begin() + i, std::back_inserter(left));
            std::copy(matrix_sizes.begin() + i, matrix_sizes.end(), std::back_inserter(right));
            int min_count_left = get_minimum_multiplication(left);
            int min_count_right = get_minimum_multiplication(right);
            int count = min_count_left +
                        min_count_right +
                        left.front().first * left.back().second * right.back().second;
            if (min_count == 0) {
                min_count = count;
            } else {
                min_count = std::min(min_count, count);
            }
        }
        memo[matrix_sizes] = min_count;
        return min_count;
    }
}

int main() {
    int n;
    std::cin >> n;
    vector<pair<int, int>> matrix_sizes(n);
    for (auto& size : matrix_sizes) {
        std::cin >> size.first >> size.second;
    }

    std::cout << get_minimum_multiplication(matrix_sizes) << std::endl;
}

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

static const int N = 100;
#define EXTREME 10000000;
int S[N+1][N+1];
int p[N+1];

void multiply(int n){
    int i;
    for(i = 1; i <= n; i++){
        S[i][i] = 0;
    }

    for(int l = 2; l <= n; l++){
        for(int i = 1; i <= n - l + 1; i++){
            int j = i + l - 1;
            S[i][j] = EXTREME;
            for(int k = i; k <= j - 1; k++){
                S[i][j] = min(S[i][j], S[i][k] + S[k+1][j] + p[i-1]*p[k]*p[j]);
            }
        }
    }
}

int main(){
    int n, i;
    cin >> n;


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

    }

    multiply(n);
    cout << S[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 <iostream>
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 <stdio.h>
#include <algorithm>
using namespace std;

typedef long long ll;
#define INF ((ll)10000000000)
#define MAX_N (110)
typedef struct {
    ll r;
    ll c;
} Mat;

int n;
Mat M[MAX_N];
ll dp[MAX_N][MAX_N];

ll dfs(int i, int j)
{
    if ( j - i == 1 ) return 0;
    else if ( dp[i][j] ) return dp[i][j];
    else {
	ll ret = INF;
	for ( int k = i + 1; k < j; k++ ) {
	    ret = min(ret, dfs(i, k) + dfs(k, j) + M[i].r * M[k].r * M[j-1].c );
	}

	return dp[i][j] = ret;
    }
}

int main()
{
    scanf("%d", &n);

    for ( int i = 0; i < n; i++ ) {
	scanf("%lld %lld", &M[i].r, &M[i].c);
    }
    
    ll ans = dfs( 0, n );
    printf("%lld\n", ans);

    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++: //matrix chain multiplication
#include<iostream>
#include<cstdio>
#include<cstdlib> //malloc
using namespace std;
#define INF 1000000001
int DP[100][100];
int *p;
int rec(int r, int c) { //what to record on DP, r番目の行列からc番目の行列まで掛け算
    int Min = INF;
    for (int i = 0; i < c - r; i++) { //どこで区切るか
        Min = min(Min, DP[r][r+i] + DP[r+i+1][c] + p[r-1]*p[r+i]*p[c]);
        //3項目は2つのDPをつなぐ計算量
    }
    return Min;
}
int main() {
    int N;
    cin >> N;
    for (int i = 1; i <= N; i++) { //matrix starts index 1, p[] starts index 0
        for (int j = 1; j <= N; j++) {
            DP[i][j] = 0;
        }
    }
    p = (int *)malloc(sizeof(int) *(N+1) ); //main()外でp使うから面倒だけど
    //N+1 -> 0 start, 最後の行列の列 p[N]
    for (int i = 0; i < N; i++) {
        cin >> p[i]; cin >> p[i+1]; //start p[2]
    }
    for (int i = 1; i < N; i++) DP[i][i+1] = p[i-1]*p[i]*p[i+1]; //2つの積
    
    int y;
    for (int k = 0; k <= N - 2; k++) {
        for (int x = 1; x <= N - 2; x++) {
            y = x+(2+k);
            if (x <= N && y <= N) DP[x][y] = rec(x, y);
        }
    }
    
    cout << DP[1][N] << endl; //最初の行列から最後の行列まで
    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;
}