Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

func nextStr() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list {
		buf.Write([]byte(fmt.Sprintf(" %d", v)))
	}
	buf.Write([]byte("\n"))
	buf.Flush()
}

//solve
//単純な場合
func matrixChainMultiplication() {
	//行列が1つだけのとき
	for i := 1; i <= n; i++ {
		m[i][i] = 0
	}
	for l := 2; l <= n; l++ {
		for i := 1; i <= n-l+1; i++ {
			j := i + l - 1
			m[i][j] = 1 << 21
			//kまでで区切る
			for 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])
			}
		}
	}
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

func min(a, b int) int {
	if a > b {
		return b
	} else {
		return a
	}
}

const MAX = 100

var n int
var p [MAX + 1]int

//m[i][j]: Mi * Mi+1 * ... * Mjを計算するときに必要なスカラー乗算の最小回数
var m [MAX + 1][MAX + 1]int

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 1; i <= n; i++ {

		p[i-1] = nextInt() //行数
		p[i] = nextInt()   //列数
	}

	matrixChainMultiplication()
	fmt.Println(m[1][n])
}

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

struct matrix_size{
	int row;
	int col;
};

int matrixchaincost(vector <matrix_size> &M){
	int n=M.size();
	vector < vector <int> > cost(n, vector <int> (n));
	vector < vector <matrix_size> > X(n, vector <matrix_size> (n));
	for (int i=0; i<n; i++){
		cost[i][i] = 0;
		X[i][i] = M[i];
	}

	for (int length=2; length<=n; length++){
		for (int i=0; i+length<=n; i++){
			int j = i+length-1;
			X[i][j].row = X[i][i].row;
			X[i][j].col = X[j][j].col;
			if (X[i][j-1].col != X[j][j].row){
				cout<<"error"<<endl;
				return NULL;
			}
			int k = i+1;
			int mincost = X[i][k-1].row * X[i][k-1].col * X[k][j].col + cost[i][k-1] + cost[k][j];
			k++;
			while (k<=j){
				int tmp = X[i][k-1].row * X[i][k-1].col * X[k][j].col + cost[i][k-1] + cost[k][j];
				if (tmp<mincost)
					mincost = tmp;
				k++;
			};
			cost[i][j] = mincost;
		}
	}
	return cost[0][n-1];
}

int main(void){
	int n;
	cin>>n;

	vector <matrix_size> M(n);

	for (int i=0; i<n; i++){
		cin>>M[i].row;
		cin>>M[i].col;
	}
	cout<<matrixchaincost(M);
	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++: #define _USE_MATH_DEFINES
#include <iostream>
#include <string>
#include <utility>
#include <stack>
#include <vector>
#include <queue>
#include <algorithm>
#include <map>
#include <climits>
#include <set>
#include <cmath>
#include <numeric>
#include <iomanip>

using namespace std;
int r[100];
int c[100];
int dp[100][100];
int main(void){
  int n;
  cin >> n;
  for(int i = 0; i < n; i++){
    cin >> r[i] >> c[i];
  }

  for(int i = 0; i < n; i++){
    for(int j = 0; j < n; j++){
      dp[i][j] = INT_MAX;
    }
  }
  for(int i = 0; i < n; i++){
    dp[i][i] = 0;
  }

  for(int i = 1; i < n; i++){
    for(int j = 0; j <= n - i - 1; j++){
      for(int k = j; k < j + i; k++){
        dp[j][j + i] = min(dp[j][j + i], dp[j][k] + dp[k + 1][j + i] + r[j] * c[k] * c[j + i]);
      }
    }
  }
  cout << dp[0][n - 1] << endl;
  return 0;
}

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

static const int N = 1000;
#define INF (1 << 20)

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

int main() {
    int n; std::cin >> n;
    for(int i = 1; i <= n; i++) {
        std::cin >> p[i-1] >> p[i];
    }
    for(int i = 0; i < N; i++) {
        for(int j = 0; j < N; j++) {
            m[i][j] = 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] = INF;
            for(int k = i; k <= j - 1; k++) {
                m[i][j] = std::min(m[i][j], m[i][k] + m[k+1][j] + p[i-1] * p[k] * p[j]);
            }
        }
    }
    std::cout << m[1][n] << std::endl;
    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;
int main(){
    int n;scanf("%d",&n);
    vector<pair<int,int>> m(n);
    for(int i=0;i<n;i++)scanf("%d%d",&m[i].first,&m[i].second);
    int dp[n][n];
    fill(dp[0],dp[0]+n*n,1e9);
    for(int i=0;i<n;i++)dp[i][i]=0;
    for(int k=1;k<n;k++){
        for(int i=0;i<n-k;i++){
            int j=i+k;
            for(int l=i;l<j;l++){
                dp[i][j]=min(dp[i][j],dp[i][l]+dp[l+1][j]+m[i].first*m[l].second*m[j].second);
            }
        }
    }
    printf("%d\n",dp[0][n-1]);
    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 <bits/stdc++.h>
#define INF 1e9
using namespace std;


int main(){
  int n;
  cin>>n;
  int a[105];
  for(int i=1;i<=n;i++)cin>>a[i-1]>>a[i];

  int dp[105][105]={};
  for(int i=0;i<105;i++)
    for(int j=0;j<105;j++)dp[i][j]=INF*(i!=j);

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

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

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

using namespace std;
static const int N = 100;

#define INT_MIN     (-2147483647 - 1) /* minimum (signed) int value */
#define INT_MAX       2147483647    /* maximum (signed) int value */

void solve(vector<int> &data)
{
	vector<vector<int> > dp(N + 1, vector<int>(N + 1, 0));

	int nums = data.size() - 1;
	for (int len = 2; len <= nums; ++len)
	{
		for (int l = 1; l <= nums - len + 1; ++l)
		{
			int r = l + len - 1;
			dp[l][r] = INT_MAX;
			for (int m = l; m <= r - 1; ++m)
			{
				cout << len << " " << l << " " << r << endl;
				dp[l][r] = min(dp[l][r], dp[l][m] + dp[m+1][r] + data[l - 1] * data[m] * data[r]);
			}
		}
	}

	cout << dp[1][nums] << endl;
}

int main()
{
	int num; cin >> num;
	vector<int> data(num + 1);
	for (int i = 1; i <= num; ++i)
		cin >> data[i-1] >> data[i];

	solve(data);
}

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

static const int maxn=44;

int DP[45];

int Fibonacci(int n) {
  if (n==0 or n==1) {
    return DP[n]=1;
  }
  if (DP[n]!=(-1)) {
    return DP[n];
  }
  return DP[n]=Fibonacci(n-1)+Fibonacci(n-2);
}
int main() {
  std::ios::sync_with_stdio(false);
  cout.tie(0);
  cin.tie(0);
  memset(DP,(-1),sizeof(DP));
  Fibonacci(maxn);
  int n;
  cin>>n;
  cout<<DP[n]<<endl;
  return 0;
}

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


int main()
{
    int n,p[101];
    cin>>n;
    for(int i=1;i<=n;i++)
        cin>>p[i-1]>>p[i];
    int m[100][100];
    for(int i=0;i<n;i++)
        m[i][i]=0;
    for(int len=2;len<=n;len++)
        for(int i=0;i<n-len+1;i++)
        {
            int j=i+len-1;
            m[i][j]=1<<20;
            for(int k=i;k<i+len-1;k++)
                m[i][j]=min(m[i][j],m[i][k]+m[k+1][j]+p[i]*p[k+1]*p[j+1]);
        }
    cout<<m[0][n-1]<<endl;
    return 0;

}