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<bits/stdc++.h>

using namespace std;

typedef long long ll;
#define endl '\n'

int n;
ll r[111],c[111],d[111];
ll dp[111][111];
const ll oo = 1000000000000000LL;

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

	cin >> n;
	for(int i = 1; i <= n; i++)
		cin >> r[i] >> c[i];
	d[0] = r[1];
	for(int i = 1; i <= n; i++)
		d[i] = c[i];
	for(int size = 1; size <= n;size++){
		for(int i = 1; i <= n - size; i++){
			int j = i + size;
			dp[i][j] = oo;
			for(int k = i; k <= j - 1;k++){
				ll cost = dp[i][k] + dp[k + 1][j] + d[i - 1]*d[k]*d[j];
				dp[i][j] = min(dp[i][j],cost);
			}
		}
	}
	
	cout << dp[1][n] << endl;

	return 0;
}

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

using namespace std;

static const int N = 100;

int main() {
    int n, P[N + 1], m[N + 1][N + 1];
    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;

    for (int l = 2; l <= n; l++) {
        for (int i = 1; i <= n - l + 1; i++) {
            int j = i + l - 1;
            m[i][j] = (1 << 21);
            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;

    return 0;
}

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

const long N = 100;

int main(){
	long n, p[N + 1], m[N + 1][N + 1];
	cin >> n;
	for (long i = 1; i <= n; i++){
		cin >> p[i - 1] >> p[i];
	}

	for (long i = 1; i <= n; i++) m[i][i] = 0;
	for (long l = 2; l <= n; l++){
		for (long i = 1; i <= n - l + 1; i++){
			long j = i + l - 1;
			m[i][j] = (1 << 21);
			for (long k = 0; k <= j - 1; k++){
				m[i][j] = min(m[i][j], m[i][k] + m[i][k] + m[k + 1][j] + p[i - 1] * p[k] * p[j]);
			}
		}
	}

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

	return 0;
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
    int DP[101][101];
    int *p;
int rec(int r,int c){
    int Min =100000001;
    
    for(int i=0;i<c-r;i++){
        Min =min(Min,DP[r][r+i] + DP[r+i+1][c]+p[r-1]*p[r+i]*p[c]);
    }
    return Min;
}
int main(void){
    int n,bb;
    cin>>n;
    p =new int[n+1];
    cin>> p[0];
    cin>>p[1];
    for(int i=1;i<=n ;i++) DP[i][i]=0;;
    for(int i=2;i<=n;i++){
        cin>>bb;
        cin>>p[i];
    }
    for(int i=1;i<n;i++){
        DP[i][i+1]=p[i-1]*p[i]*p[i+1];
    }
    for(int j=0;j<=n-3;j++){
        for(int i=3+j;i<=n;i++){
            DP[i-2-j][i] =rec(i-2-j,i);
        }
    }
    cout <<DP[1][n]<<endl;
}

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

int n;
long long a[105][105];
int in[105][2];

int main()
{
    memset(a,0,sizeof(a));
    cin>>n;
    int i;
    for(i=0;i<n;i++){
        cin>>in[i][0]>>in[i][1];
    }
    for(i=1;i<n;i++){
        int j=0;
        for(j=0;j<n-i;j++){
            int k;
            for(k=0;k<i;k++){
                long long aa=a[j][j+k]+a[j+k+1][j+i]+in[j][0]*in[j+k][1]*in[j+i][1];
                if(a[j][j+i]==0)a[j][j+i]=aa;
                else a[j][j+i]=min(a[j][j+i],aa);
            }
        }
    }
    cout<<a[0][n-1]<<endl;
    return 0;
}

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

using namespace std;

int main() {

	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>> m(n + 1, vector<int>(n + 1, 0));
	for (int i = 1; i <= n; i++) {
		m[i][i] = 0;
	}

	for (int l = 2; l <= n; l++) {
		for (int i = 1; i <= n - l + 1; i++) {
			int j = i + l - 1;
			m[i][j] = INT_MAX;
			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;
}