Go: package main

/*
連鎖行列積
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"log"
	"math"
	"os"
	"strconv"
	"strings"
)

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

type mem *[][]int

func main() {
	scanner := makeScanner(1024)
	n := eGetInt(scanner)
	p := make([]int, n+1)
	for i := 0; i < n; i++ {
		rowcol := eGetInts(scanner)
		p[i] = rowcol[0]
		p[i+1] = rowcol[1]
	}
	m := make([][]int, n)
	for i := 0; i < n; i++ {
		m[i] = make([]int, n)
	}
	// 初期値の格納
	for i := 0; i < n; i++ {
		for j := i; j < n; j++ {
			if i == j {
				m[i][j] = 0 //  同じ行列へのコストは当然0
			} else {
				m[i][j] = math.MaxInt64
			}
		}
	}

	// num : 行列の数. num == 1の場合は初期値0を格納ずみ
	for num := 2; num <= n; num++ {
		// s : スタート行列番号
		for s := 0; s+num <= n; s++ {
			// t : 終了行列番号
			t := s + num - 1
			// k : 仕切
			for k := s; k < t; k++ {
				m[s][t] = min(m[s][t], m[s][k]+m[k+1][t]+p[s]*p[k+1]*p[t+1])
			}
		}
	}
	fmt.Println(m[0][n-1])
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

type ints []int

func (s ints) String() string {
	var buf bytes.Buffer
	buf.WriteString("[")
	sep := ""
	for _, v := range s {
		buf.WriteString(fmt.Sprintf("%s%d", sep, v))
		sep = ", "
	}
	buf.WriteString("]")
	return buf.String()
}

func reverse(a ints) ints {
	r := make(ints, len(a))
	for i := 0; i < len(a); i++ {
		r[i] = a[len(a)-1-i]
	}
	return r
}
func max(a ints) (int, bool) {
	if len(a) == 0 {
		return 0, false
	}
	m := a[0]
	for _, e := range a {
		if e > m {
			m = e
		}
	}
	return m, true
}

// func min(a []int) int {
// 	m := a[0]
// 	for _, v := range a {
// 		if v < m {
// 			m = v
// 		}
// 	}
// 	return m
// }

func sum(a ints) int {
	if len(a) == 0 {
		return 0
	}
	sum := 0
	for _, e := range a {
		sum += e
	}
	return sum
}
func find(n int, a ints) int {
	for i, v := range a {
		if n == v {
			return i
		}
	}
	return -1
}

C++: #include <algorithm>
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define all(x) (x).begin(), (x).end()
#define ll long long
#define ld long double
#define INF 1000000000000000000
typedef pair<ll, ll> pll;
typedef pair<int, int> pint;

struct mat {
    int row = -1;
    int col = -1;
};

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

    int N;
    cin >> N;
    vector<mat> M(N);
    rep(i, N) {
        int a, b;
        cin >> a >> b;
        M[i].row = a, M[i].col = b;
    }

    vector<vector<ll>> dp(N + 5, vector<ll>(N + 5, INF));
    rep(i, N + 5) { dp[i][i] = 0; }

    for (int w = 1; w < N; w++) {
        for (int i = 0; i < N; i++) {
            if (i + w >= N)
                continue;
            int j = i + w;
            for (int k = i; k < j; k++) {
                ll num_pro = M[i].row * M[k].col * M[j].col;
                dp[i][i + w] =
                    min(dp[i][i + w], dp[i][k] + dp[k + 1][i + w] + num_pro);
            }
        }
    }

    cout << dp[0][N - 1] << endl;
}

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

int calcDpTable(int i, int j, int ** dpTable, const int *p) {
	int minValue = INT_MAX; 
	for (int k = i; k < j; ++k) {
		minValue = min(dpTable[i][k - i] + dpTable[k + 1][j - k - 1] + p[i] * p[k + 1] * p[j + 1], minValue);
	}
	//dpTable[0][0] = 1;
	return minValue;
}

int minNumOfMultiplications(const int *p, int n) {
	int **dpTable = new int*[n];
	for (int i = 0; i < n; ++i) {
		dpTable[i] = new int[n - i];
		dpTable[i][0] = 0;
	}

	int d = 1;
	for (int to = n - 2; to >= 0; --to) {
		for (int i = 0; i <= to; ++i) {
			int j = i + d;
			dpTable[i][j - i] = calcDpTable(i, j, dpTable, p);
		}
		++d;
	}
	int ret = dpTable[0][n - 1];
	
	for (int i = 0; i < n; ++i) {
		delete[] dpTable[i];
	}
	delete[] dpTable;

	return ret;
}

int main() {
	int n;
	cin >> n;
	int *p = new int[n + 1];
	for (int i = 0; i < n; ++i) {
		cin >> p[i] >> p[i + 1];
	}
	cout << minNumOfMultiplications(p, n) << endl;
}

C++: #include<cstdio>
#include<climits>
#include<algorithm>
using namespace std;
int AskMCM(int *p,int n){
    int cost[n+1][n+1];
    for(int i = 1;i <= n;++i) cost[i][i] =0;
    for(int l = 2;l <= n; l++){
        for(int i = 1;i <= n - l + 1;i++){
            int j = i+l -1;
            int min_cost = INT_MAX;
            for(int k = i;k < j;++k) min_cost = min(min_cost,cost[i][k] + cost[k+1][j] + p[i-1] * p[k] * p[j]);
            cost[i][j] = min_cost;
        }
    }
    return cost[1][n];
}

int main(){
    int n,r,tmp;
    scanf("%d",&n);
    int p[n+1];
    for(int i = 1;i <= n;++i) scanf("%d %d",&p[i-1],&p[i]);
    printf("%d\n",AskMCM(p,n));
}

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

int main(void){
    int n,i,k,a[110],min,x;
    
    int dp[110][110];
    int length,left,mid,right;
    
    cin>>n;
    
    cin>>a[0]>>a[1];
    for(i=2;i<n+1;i++){
        cin>>x>>a[i];
    }
    
    for(i=0;i<n;i++){
        dp[i][i]=0;
    }

    for(length=1;length<n;length++){
        for(left=0;left<n-length;left++){
            min=1000000000;
            right=left+length;
            for(mid=left;mid<right;mid++){
                x=dp[left][mid]+dp[mid+1][right]+a[left]*a[mid+1]*a[right+1];
                if(x<min)min=x;
            }
            dp[left][right]=min;
        }
    
    }

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

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

int calc(const vector<pair<int, int> >& M, int idx_b, int idx_e) {
    if (idx_b == idx_e) return 0;
    int min = 2e9;
    for (int i = idx_b; i < idx_e; i++) {
        int val = 0;
        val = calc(M, idx_b, i);
        val += calc(M, i + 1, idx_e);
        val += M[idx_b].first * M[i].second * M[idx_e].second;
        if (val < min) min = val;
    }
    return min;
}

int main(){
    int n;
    cin >> n;
    vector<pair<int, int> > M;

    for (int i = 0; i < n; i++) {
        pair<int, int> input;
        cin >> input.first >> input.second;
        M.push_back(input);
    }
    cout << calc(M, 0, M.size() - 1) << endl;

    return 0;
}

C++: #include <iostream>
using namespace std;
#define MAX_SIZE (101)

int main() {
	int n;
	cin >> n;
	// p[i-1], p[i] correspond to M[i]'s row and column size
	int p[MAX_SIZE];
	for (int i=1;i<=n;++i) {
		cin >> p[i-1] >> p[i];
	}
	// [i][j] is a cost for multiplying matrices between M[i] and M[j].
	int dp[MAX_SIZE][MAX_SIZE];
	// [i][i] = 0, i=1,...,n
	for (int i=1;i<=n;++i) {
		dp[i][i] = 0;
	}
	// [i][j], i<j, i=1,...,n
	// j - i = l-1 = 1,2,...,n-1
	// このindexの指定の仕方: なんとなくnまでに合わせたい, l=2,...,nで(l-1)=1,...,n-1になる
	// j = i + (l-1)で, i+1, ..., n まで動く.
	for (int l=2;l<=n;++l) {
		for (int i=1;i<=n-l+1;++i) {
			int j = i + l - 1;// i+1, i+2, ..., n
			dp[i][j] = (1 << 30); 
			for (int k=i;k<j;++k) {
				dp[i][j] = min(dp[i][j], dp[i][k] + dp[k+1][j] + p[i-1] * p[k] * p[j]); 
			}
		}
	}
	cout << dp[1][n] << endl;
	return 0;
}