Go: package main

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

type Matrix struct {
	r int // num of row
	c int // num of column
}

type Range struct {
	start int // index, inclusive
	end   int // index, inclusive
}

func (r Range) length() int {
	return r.end - r.start + 1
}

func calcMultiplication(x, y Matrix) (Matrix, int) {
	if x.c != y.r {
		panic("cannnot calculate")
	}
	return Matrix{x.r, y.c}, x.r * y.c * x.c
}

func calcMinMatrixChainMultiplication(matrices []Matrix, r Range, memo map[Range]int) (Matrix, int) {
	if v, ok := memo[r]; ok {
		return Matrix{matrices[r.start].r, matrices[r.end].c}, v
	}
	if r.length() == 0 {
		panic("must not be empty")
	} else if r.length() == 1 {
		return matrices[r.start], 0
	}

	var minCount int = math.MaxInt32

	for i := 0; i < r.length()-1; i++ {
		formerRange := Range{r.start, r.start + i}
		latterRange := Range{r.start + i + 1, r.end}
		matF, countF := calcMinMatrixChainMultiplication(matrices, formerRange, memo)
		matL, countL := calcMinMatrixChainMultiplication(matrices, latterRange, memo)
		_, countFL := calcMultiplication(matF, matL)
		count := countF + countL + countFL
		if count < minCount {
			minCount = count
		}
	}
	memo[r] = minCount
	return Matrix{matrices[r.start].r, matrices[r.end].c}, minCount
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	n, _ := nextInt(sc)
	matrices := make([]Matrix, n)
	for i := 0; i < n; i++ {
		r, _ := nextInt(sc)
		c, _ := nextInt(sc)
		matrices[i] = Matrix{r, c}
	}
	memo := make(map[Range]int)
	_, resultCount := calcMinMatrixChainMultiplication(matrices, Range{0, len(matrices) - 1}, memo)
	fmt.Println(resultCount)
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

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

int r[105];
int c[105];
int cache[105][105];

int f(int a, int b) {
    if (a == b) return 0;
    if (cache[a][b] == -1) {
        cache[a][b] = 2000000000;
        for (int i = a; i < b; i++) {
            int res = f(a, i) + f(i + 1, b) + r[a] * c[i] * c[b];
            if (res < cache[a][b]) cache[a][b] = res;
        }
    }
    return cache[a][b];
}

int main(void) {
    int n;
    scanf("%d",&n);
    for (int i = 0; i < n; i++) scanf("%d %d",&r[i], &c[i]);
    memset(cache, -1, sizeof(cache));
    printf("%d\n",f(0,n-1));
}

C++: #include<iostream>
using namespace std;
int dp[101][101];
class point {
public: int x, y;
};
point p[101];
int n;
int solve(int left, int right) {
	if (left == right) return dp[left][right] = 0;
	if (dp[left][right]) return dp[left][right];
	else
	{
		int min = 1<<29;
		for (int i = left; i < right; i++) {
			int k = dp[left][i] + dp[i + 1][right] + p[left].x * p[i + 1].x * p[right].y;
			if (k < min) min = k;
		}
		 dp[left][right] = min;
		 return min;
	}
}
int main(void) {
	cin >> n;
	for (int i = 0; i < n; i++) {
		cin >> p[i].x>>p[i].y;
	}
	for(int l=1;l<n; l++)
	for (int i = 0; i < n; i++) {
		if (i + l < n)
		{
			solve(i, i + l);
		}
	}
	cout << dp[0][n - 1]<<endl;
}

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

#define int long long
 
#define rep(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)

#define YES puts("YES")
#define Yes puts("Yes")
#define NO  puts("NO")
#define No  puts("No")
#define ALL(v) (v).begin(), (v).end()
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

//*
#define mod 1000000007 /*/
#define mod 998244353 //*/

typedef pair<int, int> P;
#define INF (1LL<<60)



void solve(){
    int N;
    cin >> N;
    vector<int> p(N+1,0);
    for(int i=0; i<N; i++)
        cin >> p[i] >> p[i+1];
    
    vector<vector<int>> dp(N+1, vector<int>(N+1,0));
    
    for(int w=2; w<=N; w++){
        for(int i=1; i<=N-w+1; i++){
            int j=i+w-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] + p[i-1]*p[k]*p[j]);
            }
        }
    }
    cout << dp[1][N] << endl;
}


signed main(){
    cout << fixed << setprecision(18);
    cerr << fixed << setprecision(18);
    solve();
}

C++: #include <cstdio>
#include <cstdlib>
#include <cassert>
#include <memory.h>
#include <iostream>
#include <vector>
#include <string>
#include <ctime>
#include <cstdlib>
#include <sstream>
#include <bitset>
#include <cassert>
typedef unsigned long long ull;
typedef unsigned long ul;
#define rep(i,n) for(unsigned long long i = 0;i<n;i++)
#define clear(c) memset(c,0,sizeof(c))
#define clearm(c) memset(c,-1,sizeof(c))
using namespace std;

int main(){
	int n;

	cin >> n;
	ull dp[10+1][10+1];
	clearm(dp);
	ull r[n],c[n];
	rep(i,n){
		int rr,cc;
		cin >> rr >> cc;
		r[i] = rr;
		c[i] = cc;
	}
	rep(i,n-1){
		dp[i][i+1] = r[i] * c[i+1] * r[i+1];
	}
	rep(i,n){
		dp[i][i] = 0;
	}
	for(int dif = 2;dif<n;dif++){
		for(int i = 0;i + dif<n;i++){
			for(int j = i + 1;j <= i +dif - 1;j++){
				dp[i][i+dif] = min(dp[i][i+dif],dp[i][j] + dp[j+1][i+dif] + r[i] * c[j] * c[i+dif]);
			}
		}
	}
	cout << dp[0][n-1] << endl;
	return 0;
}

C++: #include <iostream>
#include <algorithm>
using namespace std;

#define N 100

int M[101][101], p[101], n;

int solve()
{
	int l, i, j, k;
	for (l = 2; l <= n; l++) {
		for (i = 1; i <= n - l + 1; i++) {
			j = i + l - 1;
			M[i][j] = 1 << 30;
			for (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]);
		}
	}
	return M[1][n];
}

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

	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;

	cout << solve() << endl;
	return 0;
}

C++: #include<iostream>
#include<math.h>
#include<algorithm>
#include<stdint.h>
#include<vector>
#include<deque>
#include<stack>
#include<string>
#include<cstring>
#include<time.h>
#include<iomanip>
#include<list>
#include<set>
#include<unordered_map>
#include<unordered_set>
#include<random>
#include<bitset>
#include <queue>
#include <map>


using namespace std;
using ll = long long;
using ull = unsigned long long;
using uint = unsigned int;
using ldouble = long double;


#define repi(i,a,b) for(ll i = (a); i < (b); i++)
#define rep(i, n) for(ll i = 0; i < (n); ++i)


ll MOD = 1000000007;
ll inf = 1e18;
int main() {
	int N;
	cin >> N;
	vector<ll> R(N + 1);
	vector<ll> C(N + 1);
	repi(i, 1, N + 1) cin >> R[i] >> C[i];
	vector<vector<ll>> dp(N + 1);
	rep(i, N + 1) {
		dp[i].resize(N + 2);
		rep(j, N + 2)dp[i][j] = (i == j || i +1 == j) ? 0 : inf;
	}
	repi(x, 2, N+1) {
		repi(r, 1, N + 1) {
			int l = r + x;
			if (l > N + 1) break;
			ll m = inf;
			repi(j, r + 1, l) {
				m = min(m, dp[r][j] + dp[j][l] + (R[r] * R[j] * C[l - 1]));
			}
			dp[r][l] = m;
		}
	}
	cout << dp[1][N + 1] << endl;
	return 0;
}

C++: #include <iostream>
using namespace std;
int n, a[111], b[111], dp[111][111];
int main() {
	cin >> n;
	for(int i = 0; i < n; i++) cin >> a[i] >> b[i];
	for(int i = 2; i <= n; i++) {
		for(int j = 0; j <= n - i; j++) {
			int l = j, r = j + i; // [l, r)
			dp[l][r] = 999999999;
			for(int k = l + 1; k < r; k++) {
				dp[l][r] = min(dp[l][r], dp[l][k] + dp[k][r] + a[l] * a[k] * b[r]);
			}
		}
	}
	cout << dp[0][n] << endl;
}