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 <iostream>
#include <stdio.h>
//#include <string.h>

using namespace std;

struct Matrix{
    int row;
    int col;
    int total;
};

Matrix mts[100][100];
int n;

int main()
{
    scanf("%d",&n);
    for(int i=0; i<n; ++i){
        int r,c;
        scanf("%d %d", &r, &c);
        mts[0][i].row = r;
        mts[0][i].col = c;
        mts[0][i].total = 0;
    }

    for(int i=1; i<n; ++i){
        for(int j=0; j<n-i; ++j){
            int min = 0xfffffff;
            mts[i][j].row = mts[i-1][j].row;
            mts[i][j].col = mts[0][i+j].col;
            for(int k=0; k<i; ++k){
                int tmp = mts[k][j].total + mts[i-k-1][k+j+1].total + mts[k][j].row * mts[i-k-1][k+j+1].row * mts[i-k-1][k+j+1].col;
                min = min < tmp ? min : tmp;
            }
            mts[i][j].total = min;
        }
    }

    cout << mts[n-1][0].total << endl;

    return 0;
}

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

using namespace std;


int main()
{
    int n;
    int p[101];
    int m[101][101];

    cin >> n;

    for (int i = 0; i <= n; i++)
        for (int j = 0; j <= n; j++)
            m[i][j] = 0;

    for (int i = 0; i < n; i++)
        cin >> p[i] >> p[i + 1];

    for (int len = 1; (n - 1) - len >= 0; len++) {
        for (int i = 0; i <= (n - 1) - len; i++) {
            m[i][i + len] = INT_MAX / 3;
            for (int j = i; j < i + len; j++) {
                m[i][i + len] = min(m[i][i + len], m[i][j] + m[j + 1][i + len] + p[i] * p[j + 1] * p[i + len + 1]);
            }
        }
    }

    cout << m[0][n - 1] << endl;

    return 0;
}