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


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

void matrixChainMultiplication() {
    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 ; 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;
}

int main() {
    // 制約見て！！！デカかったらlong longにすること！
    cin >> n;
    int _;
    rep(i, n) {
        if(i == 0) {
            scanf("%d %d", &p[i], &p[i + 1]);
        } else {
            scanf("%d %d", &_, &p[i + 1]);
        }
    }
    matrixChainMultiplication();
    return 0;
}

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


#define min(a, b) ((a) < (b) ? (a) : (b))

int N;
const int MAX_N = 110;
const int INF = 0x3fffffff;
int A[MAX_N];
int B[MAX_N];
int dp[MAX_N][MAX_N];

void init() {
    for(int i = 0; i < N; ++i)
        scanf("%d%d",&A[i], &B[i]);
    for(int i = 0 ;i < N; ++i)
        for(int j = 0; j < N; ++j)
            dp[i][j] = INF;
    for(int i = 0; i < N; ++i)
        dp[i][i] = 0;
}

int solve() {
    for(int k = 1; k < N; ++k) {
        for(int i = 0; i < N - k; ++i) {
            for(int j = i; j < i + k; ++j) {
                int sz = A[i] * B[j] * B[i + k];
                dp[i][i + k] = min(dp[i][i + k],dp[i][j] + dp[j+1][i + k] + sz);
            }
        }
    }
    // for(int i = 0; i < N; ++i) {                                                                                                                                              
    //  for(int j = 0; j < N; ++j)                                                                                                                                               
    //      printf("%d ", dp[i][j]);                                                                                                                                             
    //  printf("\n");                                                                                                                                                            
    // }                                                                                                                                                                         
    return dp[0][N - 1];
}

int main() {
    while(scanf("%d",&N) == 1) {
        init();
        printf("%d\n", solve());
    }
    return 0;
}

C++: #include <iostream>
#include <cstring>

int min_count[100][100];

int count(int *r, int *c, int start, int end) {
    if (min_count[start][end] != 0) {
        return min_count[start][end];
    }
    if (end - start == 0) {
        return 0;
    }
    int min = 1000000;
    for (int i = start; i < end; i++) {
        min = std::min(min, count(r, c, start, i) + r[start] * c[i] * c[end] + count(r, c, i + 1, end));
    }
    min_count[start][end] =min;
    return min_count[start][end];
}

int main() {
    std::memset(min_count, 0, sizeof(min_count));
    int n;
    std::cin >> n;
    int r[n], c[n];
    for (int i = 0; i < n; i++) {
        std::cin >> r[i] >> c[i];
    }

    std::cout << count(r, c, 0, n - 1) << std::endl;
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;

static const int N = 100;
int p[N+1];
int m[N+1][N+1];

int main(){
    int h;
    cin >> h;
    for(int i = 0; i < h; i++){
        cin >> p[i] >> p[i+1];
    }

    for(int i = 1; i <= h; i++) m[i][i] = 0;

    // lはこれから計算する行列積を成す行列の数2->h(DP)
    for(int l = 2; l <= h; l++){
        // iはこれから計算する行列積の先頭の行列
        for(int i = 1; i <= h-l+1; i++){
            // jはこれから計算する行列積の末尾の行列(これを含む)
            int j = i + l -1;
            m[i][j] = 1<<30;
            for(int k = i; k < j; 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][h] << 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; 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;
}