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++: //还需复习复习 
#include <iostream>

using namespace std;

const int N = 100; //最多矩阵个数 

int main() {
	int n;
	cin >> n;
	//储存连续相乘矩阵的行列 ，由矩阵相乘的性质，(r1*c1)*(c1*c2) = r1 * c2,因此不必重复存储中间的列或行 
	int *p = new int[n+1];
	int m[N+1][N+1] = {0}; //m[i][j] 存储着矩阵Mi*Mi+1*Mi+2*...*Mj的最少乘法次数
	for (int i=1;i<=n;i++) {
		cin >> p[i-1] >> p[i];
	}
	for (int l = 2;l<=n;l++) { //规模从2开始增加，先计算两两矩阵之间的代价 ，再计算三三矩阵之间的代价，四四之间的代价...
	    for (int i = 1;i<=n-l+1;i++) {
	    	int j = i + l -1;
	    	m[i][j] = 1 << 21; //先随便赋值一个大数，便于比较
	    	
	    	//此处与传递关系矩阵闭包有异曲同工之妙 
			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;
	delete[] p; 
	return 0;
}

C++: #include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
int main(){
    int n=0;
    scanf("%d",&n);
    int A[101];
    int dp[101][101];
    int INF=1<<30;
    memset(dp,INF,sizeof(dp));
    memset(A,0,sizeof(A));
    for(int i=1;i<=n;i++){
        scanf("%d",&A[i-1]);
        scanf("%d",&A[i]);
    }
    for(int i=1;i<=n;i++){
        dp[i][i]=0;
    }
    for(int l=2;l<=n;l++){
        for(int i=1;i<=n-l+1;i++){
            int j=i+l-1;
            dp[i][j]=INF;
            for(int k=i;k<=j-1;k++){
                dp[i][j]=min(dp[i][j],dp[i][k]+dp[k+1][j]+A[i-1]*A[k]*A[j]);
            }
        }
    }
    printf("%d\n",dp[1][n]);
    return 0;
}

C++: // ?????¬???????????¬??????

#include <iostream>
#include <iomanip>
#include <cstdio>
#include <string>
#include <cstring>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <complex>
#include <cmath>
#include <limits>
#include <cfloat>
#include <climits>
#include <ctime>
#include <cassert>
#include <numeric>
#include <functional>
using namespace std;

#define rep(i,a,n) for(int (i)=(a); (i)<(n); (i)++)
#define repq(i,a,n) for(int (i)=(a); (i)<=(n); (i)++)
#define repr(i,a,n) for(int (i)=(a); (i)>=(n); (i)--)
#define int long long int

template<typename T> void chmax(T &a, T b) {a = max(a, b);}
template<typename T> void chmin(T &a, T b) {a = min(a, b);}
template<typename T> void chadd(T &a, T b) {a = a + b;}

typedef pair<int, int> pii;
typedef long long ll;

int dx[] = {0, 0, 1, -1};
int dy[] = {1, -1, 0, 0};
constexpr ll INF = 1001001001001001LL;
constexpr ll MOD = 1000000007LL;

int N;
int R[110], C[110];

// [i, j) ???????????????????????°????°?
int dp[110][110];

signed main() {
    cin >> N;
    rep(i,0,N) cin >> R[i] >> C[i];
    repq(i,0,N) {
        repq(j,0,N) {
            if(i < j && j-i != 1) {
                dp[i][j] = dp[i][j-1] + R[i] * R[j-1] * C[j-1];
                // printf("dp[%lld][%lld] = %lld\n", i, j, dp[i][j]);
            }
        }
    }

    repq(i,3,N) {
        rep(j,0,N-i+1) {
            rep(k,j+1,j+i) {
                chmin(dp[j][j+i], 
                      dp[j][k] + dp[k][j+i] + R[j] * R[k] * C[j+i-1]);
            }
        }
    }
    cout << dp[0][N] << endl;
    return 0;
}

C++: #include <iostream>
#include <cstdlib>
#include <cstdio>

using namespace std;

typedef struct matrix{
  int row;
  int column;
  struct matrix *next;
  struct matrix *back; 
}Matrix;

Matrix *push_back(Matrix *begin, int row, int column) {
  Matrix *p = (Matrix*)malloc(sizeof(Matrix));
  p->row = row;
  p->column = column;
  p->next = NULL;
  p->back = NULL;
  if(begin == NULL) return p;
  Matrix *p2 = begin;
  while(p2->next != NULL) p2 = p2->next;
  p2->next = p;
  p->back = p2;
  return begin;
}

Matrix *product_count(Matrix *x, int type, long *count) {
  Matrix *a,*b;
  if(type == 0) {
    a = x->back;
    b = x;
  }
  else {
    a = x;
    b = a->next;
  }
  *count = 0;
  if(a == NULL || b == NULL) return x;
  *count += a->row * a->column * b->column;
  Matrix *c = (Matrix*)malloc(sizeof(Matrix));
  c->row = a->row;
  c->column = b->column;
  c->next = b->next;
  c->back = a->back;
  if(a->back != NULL) a->back->next = c;
  if(b->next != NULL) b->next->back = c;
  free(a);
  free(b);
  return c;
}

int main()
{
  int i,n,r,c;
  Matrix *begin = NULL;
  scanf("%d",&n);
  for (i = 0; i < n; i++) {
    scanf("%d %d",&r,&c);
    begin = push_back(begin,r,c);
  }
  Matrix *min = begin, *p = begin;
  while (p->next != NULL) {
    if(min->column > p->column) min = p;
    p = p->next;
  }
  long sum = 0,count;
  if(min->column <= begin->row) {
    begin = NULL;
    while(1) {
      min = product_count(min,0,&count);
      if(count != 0) sum += count;
      else break;
    }
    if(min->next != NULL) {
      min = min->next;
      while(1) {
	min = product_count(min,1,&count);
	if(count != 0) sum += count;
	else break;
      }
      min = product_count(min,0,&count);
      sum += count;
    }
  }
  else{
    min = begin;
    begin = NULL;
    while(1) {
      min = product_count(min,1,&count);
      if(count != 0) sum += count;
      else break;
    }
  }
  cout << sum << endl;
  
  return 0;
}