Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

//util
var sc = bufio.NewScanner(os.Stdin)

func nextStr() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list {
		buf.Write([]byte(fmt.Sprintf(" %d", v)))
	}
	buf.Write([]byte("\n"))
	buf.Flush()
}

//solve
//単純な場合
func matrixChainMultiplication() {
	//行列が1つだけのとき
	for i := 1; i <= n; i++ {
		m[i][i] = 0
	}
	for l := 2; l <= n; l++ {
		for i := 1; i <= n-l+1; i++ {
			j := i + l - 1
			m[i][j] = 1 << 21
			//kまでで区切る
			for 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])
			}
		}
	}
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

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

const MAX = 100

var n int
var p [MAX + 1]int

//m[i][j]: Mi * Mi+1 * ... * Mjを計算するときに必要なスカラー乗算の最小回数
var m [MAX + 1][MAX + 1]int

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 1; i <= n; i++ {

		p[i-1] = nextInt() //行数
		p[i] = nextInt()   //列数
	}

	matrixChainMultiplication()
	fmt.Println(m[1][n])
}

C++: #include "bits/stdc++.h"
#include <unordered_set>

#define _CRT_SECURE_NO_WARNINGS

#define REP(i, n) for(decltype(n) i = 0; i < (n); i++)
#define REP2(i, x, n) for(decltype(x) i = (x); i < (n); i++)
#define REP3(i, x, n) for(decltype(x) i = (x); i <= (n); i++)
#define RREP(i, n) for (decltype(n) i = (n) - 1; i >= 0; i--)

#define ALL(a) (a).begin(),(a).end()
#define SORT(c) sort((c).begin(),(c).end())
#define DESCSORT(c) sort(c.begin(), c.end(), greater<int>())

using namespace std;

const int INF = 1000000000;
const double PI = 3.1415926535897932384626433832795;

// N, E, S, W
const int dx[4] = { -1, 0,  1,  0 };
const int dy[4] = { 0, 1,  0, -1 };

using LL = long long int;
using LD = long double;
using pii = pair<int, int>;
using pdd = pair<double, double>;
using pll = pair<LL, LL>;
using vi = vector<int>;
using vd = vector<double>;
using vvi = vector<vi>;
using vll = vector<LL>;

//==============================================

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

	
	int n;
	cin >> n;

	vi p(150);
	REP3(i, 1, n) {
		cin >> p[i - 1] >> p[i];
	}

	vvi m(150, vi(150));
	REP3(i, 1, n) m[i][i] = 0;
	REP3(l, 2, n) {
		REP3(i, 1, n - l + 1) {
			int j = i + l - 1;
			m[i][j] = (1 << 21);
			REP3(k, i, j - 1) {
				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] << "\n";
	return 0;
}

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];
}