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 <bits/stdc++.h>
using namespace std;
long long dp[1005][1005];
long long a[1005];
long long b[1005];
int main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
//	freopen("a.txt","r",stdin);
	int n;cin>>n;
	for(int i=1;i<=n;i++)
		cin>>a[i]>>b[i];
	memset(dp,0xc,sizeof(dp));
	for(int i=1;i<=n;i++)dp[i][i]=0;
	for(int l=1;l<n;l++){
		for(int i=1;i<=n;i++){
			int j=i+l;
			if(j>n)continue;
			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]*b[j]);
		}
	}		
	cout<<dp[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>
#include <limits>
using namespace std;

int M[101][101] = {};
int p[101];

int matrixChain(int n)
{
    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] = std::numeric_limits<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]);
                //cout << M[1][n] << endl;
            }
        }
    }

    return M[1][n];
}

int main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

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

    cout << matrixChain(n) << endl;

    return 0;
}

C++: #include<iostream>
#include<cassert>
using namespace std;
struct mat
{
	int w;
	int h;
};
typedef struct mat mat_t;
int mulnum(mat_t,mat_t);
long long min(long long a,long long b);

int n;
mat_t a[101];
long long dp[101][101] ;

int main(){
	cin >> n;
	for(int i=0;i<n;i++){
		cin >> a[i].h >> a[i].w;
	}
	for(int x = 0;x<n;x++){
		for(int y =0;y<n;y++){
			dp[x][y] = 2000000;
			if(x == y) dp[x][y] = 0;
		}
	}
	int i = 0;
	int j = 1;
	for(int l = 1;l<n;l++){
		i = 0;
		for(j=l;j<n;j++){
			for(int k = i;i <= k && k < j;k++){
				dp[i][j] = min(dp[i][j],dp[i][k] + dp[k+1][j] + a[i].h *a[k].w * a[j].w);
			}
			i++;
		}
	}
	/*
	for(int x = 0;x<n;x++){
		for(int y=0;y<n;y++){
			cerr << dp[x][y] << " ";
		}
		cerr << endl;
	}
	*/
	cout << dp[0][n-1] << endl;
}

int mulnum(mat_t a,mat_t b){
	assert(a.h == b.w);
	return a.h*a.w*b.h;
}

long long min(long long a,long long b) {
	return a<b? a:b;
}

C++: #include <string>
#include <utility>
#include <iostream>
 
#define MAX 100

#define INF 100000000

int left[MAX];
int right[MAX];

int DP[MAX][MAX];

int main(){
  int n;
  std::cin >> n;

  for(int i = 0; i < n; i++){
    std::cin >> left[i];
    std::cin >> right[i];
  }
  
  for(int i = 0; i < MAX; i++){
    for(int j = 0; j < MAX; j++){
      DP[i][j] = INF;
   }
  }

  for(int k = 0; k < n; k++){
    for(int l = 0; l + k < n; l++){
      int r = l + k;
      
      if(k == 0){
	DP[l][r] = 0;
      }else if(k == 1){
	DP[l][r] = left[l] * right[l] * right[r];
      }else{
	for(int t = l; t < r; t++){
	 
	  DP[l][r] = std::min(DP[l][r], DP[l][t] + DP[t + 1][r] + left[l] * right[t] * right[r]);
	}

	// printf("%d %d %d\n", l, r, DP[l][r]);
      }
    }
  }
  
  std::cout << DP[0][n - 1] << std::endl;
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
static const int A=100;
int main(){
    int n,p[A+1],m[A+1][A+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 j=2; j<=n; j++){
        for(int i=1;i<=n-j+1;i++){
        int l=i+j-1;
        m[i][l]=(1<<21);
        for(int x=i;x<=l-1;x++){
            m[i][l]=min(m[i][l],m[i][x]+m[x+1][l]+p[i-1]*p[x]*p[l]);
        }
        }
    }
cout<<m[1][n]<<endl;
return 0;
}

C++: #include <iostream>

using namespace std;

int main() {
  // 初期化
  int n;
  cin >> n;
  int m[110][110];
  int p[110];
  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<algorithm>
using namespace std;

static const int N = 100;

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

   return0;
}

C++: #include<stdio.h>

int matrixChainOrder(int *p);
int m[101][101];
int n1;
int main(){
  
  int i,r,c,min;
  int p[100];
  scanf("%d",&n1);

  for(i=0;i<n1;i++){
    scanf("%d %d",&r,&c);
    if(i==n1-1) p[n1]=c;
    p[i]=r;
  }

  min = matrixChainOrder(p);
  printf("%d\n",min);

  return 0;
}

int matrixChainOrder(int *p){
  int n2,l,i,j,q,k;
  
  n2 = n1 - 1;
  for(i=1;i<=n2;i++){
    m[i][i] = 0;
  }
  for(l=2;l<=n2;l++){ 
    for(i=1;i<=n2-l+1;i++){ 
      j = i+l-1;
      m[i][j] = 1.0/0.0;
      for(k=i;k<j;k++){
	q = m[i][k] + m[k+1][j]+p[i-1]*p[k]*p[j];
        if(m[i][j]>=q)  m[i][j] = q;
      }
    }
  }
  return m[i][j];
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
#define N (100)

int main(void){
    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=0;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;
}