🐹 + 🔧 Advanced Tier: Go + C

/**
 * Advanced Tier: Go + C Integration (CGO)
 * This program demonstrates Go calling C code via CGO
 * Use case: Leveraging existing C libraries with Go's concurrency
 */

package main

/*
#include <stdlib.h>
#include <math.h>

// C function: Fast prime number checking
int is_prime_c(long long n) {
    if (n < 2) return 0;
    if (n == 2) return 1;
    if (n % 2 == 0) return 0;
    
    long long sqrt_n = (long long)sqrt((double)n);
    for (long long i = 3; i <= sqrt_n; i += 2) {
        if (n % i == 0) return 0;
    }
    return 1;
}

// C function: Array sum (SIMD-style optimization possible)
double array_sum_c(double* arr, int size) {
    double sum = 0.0;
    for (int i = 0; i < size; i++) {
        sum += arr[i];
    }
    return sum;
}
*/
import "C"

import (
    "fmt"
    "sync"
    "time"
)

// Go wrapper for C prime checking
func isPrimeC(n int64) bool {
    return C.is_prime_c(C.longlong(n)) == 1
}

// Go native implementation for comparison
func isPrimeGo(n int64) bool {
    if n < 2 {
        return false
    }
    if n == 2 {
        return true
    }
    if n%2 == 0 {
        return false
    }

    for i := int64(3); i*i <= n; i += 2 {
        if n%i == 0 {
            return false
        }
    }
    return true
}

// Run parallel prime checking (Go concurrency + C computation)
func parallelPrimeCheck(numbers []int64) []bool {
    results := make([]bool, len(numbers))
    var wg sync.WaitGroup

    // Use Go's goroutines with C's computation
    for i, num := range numbers {
        wg.Add(1)
        go func(idx int, n int64) {
            defer wg.Done()
            results[idx] = isPrimeC(n) // C function called from goroutine
        }(i, num)
    }

    wg.Wait()
    return results
}

func main() {
    fmt.Println("=" + strings.Repeat("=", 59))
    fmt.Println("🐹 + 🔧 GO + C INTEGRATION (CGO)")
    fmt.Println("Advanced Tier: Go Concurrency with C Performance")
    fmt.Println("=" + strings.Repeat("=", 59))
    
    // Demonstrate Go concurrency with C computation
    numbersToCheck := []int64{
        1000000007, 1000000009, 1000000021, 1000000033,
    }
    
    start := time.Now()
    results := parallelPrimeCheck(numbersToCheck)
    duration := time.Since(start)
    
    fmt.Printf("Checked %d numbers in parallel: %v\n", 
        len(numbersToCheck), duration)
    
    for i, num := range numbersToCheck {
        fmt.Printf("  %d: %v\n", num, results[i])
    }
    
    fmt.Println("\n✨ Languages Used:")
    fmt.Println("  🐹 Go  - Concurrency, memory management")
    fmt.Println("  🔧 C   - Performance, existing libraries")
    fmt.Println("  🔗 CGO - Bridge between Go and C")
}