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 <stdio.h>
#include <iostream>
#include <string>
using namespace std;
#define NUM 100
#define INF 1000000000

int X_dim[NUM];
int Y_dim[NUM];
int M[NUM][NUM];

void init(){
    for(int i = 0; i < NUM; i++){
        for(int j = 0; j < NUM; j++){
            if(i == j){
                M[i][j] = 0;
            }else{
                M[i][j] = INF;
            }
        }
    }

}

int main(void){
    init();

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

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

    for(int k = 1; k <= n - 1; k++){
        for(int x = 0; x + k <= n - 1; x++){
            for(int t = x; t <= x + k - 1; t++){
                M[x][x + k] = min(M[x][x + k], M[x][t] + M[t + 1][x + k] + X_dim[x] * Y_dim[t] * Y_dim[x + k]);
                // printf("M[%d][%d]: M[%d][%d] + M[%d][%d] + %d * %d * %d\n", x, x + k, x,t,t+1,x+k,X_dim[x],Y_dim[t],Y_dim[x+k]);
            }
        }
    }

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

C++: #include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < n; i++)
using namespace std;
typedef long long ll;

int dp[100][100];

int main(void)
{   
    int n;
    cin >> n;
    pair<int, int> rc[n];
    rep(i, n) cin >> rc[i].first >> rc[i].second;

    vector<vector<int> > dp(n, vector<int>(n, 1e9));
    
    rep(i, n) {
        dp[i][i] = 0;
    }

    for(int i = 1; i <= n-1; i++) {
        for(int j = 0; j <= n - 1 - i; 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] + rc[j].first*rc[k].second*rc[j+i].second);
            }
        }
    }

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

C++: #include "bits/stdc++.h"
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 <cstdio>
#include <algorithm>
#include <vector>
#include <utility>
#include <queue>
#include <climits>
using namespace std;

int mcm(vector<int>& p)
{
    vector<vector<int> > m(p.size() - 1, vector<int>(p.size() - 1));
    for (int i = 0; i < m.size(); i++) {
        m[i][i] = 0;
    }
/*
 * l == number of targets
 * i == left most of targets
 */
    for (int l = 2; l <= m.size(); l++) {
        for (int i = 0; i < m.size() - l + 1; i++) {
            int j = i + l - 1;
            m[i][j] = INT_MAX;
            for (int k = i; k < j; k++) {
                m[i][j] =
                    min(m[i][j],
                        m[i][k] + m[k + 1][j] + p[i] * p[k + 1] * p[j + 1]);
            }
        }
    }
    return m[0][m.size() - 1];
}

int main()
{
    int n;
    cin >> n;
    vector<int> p(n + 1);
    for (int i = 1; i < n + 1; i++) {
        cin >> p.at(i - 1) >> p.at(i);
    }
    cout << mcm(p) << 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[i][k]+m[k+1][j]+p[i-1]*p[k]*p[j]);
}
}
}
cout << m[1][n]<< endl;

return 0;

}

C++: #include <iostream>
#include <algorithm>
#include <cstdio>
#include <cmath>
#include <string>
#include <cctype>
#include <stack>
#include <queue>
#include <vector>
#include <cstdlib>
#include <list>
#define _USE_MATH_DEFINES
#include <math.h>

using namespace std;

int main() {

	int n, p[101], m[101][101];

	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 i = 2; i <= n; i++) {
		for (int j = 1; j <= n; j++) {
			int k = i + j - 1;
			m[j][k] = (1 << 21);
			for (int l = j; l <= k - 1; l++) {
				m[j][k] = min(m[j][k], m[j][l] + m[l + 1][k] + p[j - 1] * p[l] * p[k]);
			}
		}
	}

	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
struct MX{
	int r,c;
} mx[105];
long long dp[105][105];
int main()
{
	int n; cin>>n;
	for(int i=1;i<=n;i++){
		cin>>mx[i].r>>mx[i].c;
	}
	for(int i=i;i<=n;i++) dp[i][i] = 0;
	for(int k=1;k<n;k++){
		for(int i=1;i<=n-k;i++){
			int j = i+k;
			long long mini=1e19,t;
			for(int a=i;a<j;a++){
				t = dp[i][a]+dp[a+1][j]+mx[i].r*mx[a].c*mx[j].c;
				mini = min(mini,t);
			}
			dp[i][j] = mini;
		}
	}
	cout<<dp[1][n]<<endl;
	return 0;
}