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++: // http://algorithms.blog55.fc2.com/blog-entry-66.html

#include <iostream>
using namespace std;
#include <stdio.h>
#include <string.h>

#define M 100

int N,R[M+1],C[M][M],B[M][M];

void compute(){
	int i=0,j,k,cost;
	memset(C,99,sizeof(C));
	for(;i<N;i++)C[i][i]=0;
	for(j=1;j<N;j++)
		for(i=0;i<N - j; i++ )
			for (k = i; k < i + j; k++ ){
				cost = C[i][k] + C[k+1][i+j] + R[i]*R[k+1]*R[i+j+1];
				if(cost<C[i][i+j])C[i][i+j]=cost,B[i][i+j]=k; 
			}
}

void order( int i, int j ){
	if ( i == j ) cout << "M" << i;
	else{
		cout << "(";
		order( i, B[i][j]-1 ); order(B[i][j], j);
		cout << ")";
	}
}

void input(){
	cin >> N;
	int z,i=0;
	for (; i < N; i++ ) cin >> R[i]>>z;
	R[i]=z;
	//SIZE++;
}

void output(){
	cout <<  C[0][N-1] << endl;
	//order(0, N);
	//cout << endl;
}

main(){
	input();
	compute();
	output();
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <string>
#include <set>
#include <queue>
#include <stack>
#include <tuple>
#include <cmath>
#include <iomanip>
#include <map>
#include <cstring> //memset(dp,0,sizeof(dp))
#include <functional>
#include <cctype>
#include <locale>
#define ll long long
#define rep(i,n) for(int i=0;i<(n);i++)
#define rrep(i,n) for(int i=n-1;i>=0;i--)
#define fi first
#define se second
#define pb push_back
#define ALL(a) (a).begin(),(a).end()
using namespace std;
template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}
typedef pair<int,int> P;
typedef pair<long long,long long> Pll;
#define fout(num) cout << fixed << setprecision(20) << (num) << endl
//s[i]=tolower(s[i]); islower(s[i]); cout << tolower(s[i])はバグ
//vector<vector<ll>> dp(n,vector<ll>(n))
//exist x map o setconst ll MOD = 1e9+7;return fac[n]*(finv[k]*finv[n-k] % MOD) % MOD;
const ll INF = 1e18;
signed main(){
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int n; cin >> n;
    ll dp[n][n];
    rep(i,n)rep(j,n)dp[i][j]=INF;
    rep(i,n) dp[i][i]=0;
    ll c[n],r[n];
    rep(i,n){
        cin  >> r[i] >> c[i];
    }
    for(int num=2;num<=n;num++){
        for(int i=0;i<n;i++){
            int j=i+num-1;
            if(j<0||n<=j) continue;
            for(int k=i;k<j;k++){
                dp[i][j]=min(dp[i][j],dp[i][k]+dp[k+1][j]+r[i]*c[k]*c[j]);
            }
        }
    }
    cout<< dp[0][n-1]  << endl;
}

C++: #include <stdio.h>
#include <math.h>

int matrixChainMultiplication(int *);

int n;

int main(){
  int i,A[101],l,j,k;

  scanf("%d",&n);
  for(i=1;i<=n;i++){
    scanf("%d",&A[i-1]);
    scanf("%d",&A[i]);
  }
  printf("%d\n",matrixChainMultiplication(A));


}
int matrixChainMultiplication(int *A){
  int i,l,j,k,P[101][101],g;
  for(i=1;i<n;i++){
    P[i][i]=0;
  }
  for(l=2;l<=n;l++){
    for(i=1;i<=n-l+1;i++){
      j=i+l-1;
      P[i][j]=9999999;
      for(k=i;k<=j-1;k++){
	g=P[i][k]+P[k+1][j]+A[i-1]*A[k]*A[j];
	if(g<P[i][j])
	  P[i][j]=g;
	  
      }
    }
  }

  return P[1][n];
}