#include <stdio.h>
#include <stdint.h>
#include <math.h>

// Pingala's Chandas Shastra: Binary number system
// Generates all possible meters (binary strings) of length n
// This is identical to:
// 1. Activation pattern search in neural networks
// 2. Beam search initialization
// 3. Feature combination enumeration

// Pingala's recursive rule (Sutra):
// "Parvarya dvirardhe" - Double at each step, with half for the next

// Generate all binary patterns of length n (Pingala's method)
void pingala_meters(int n) {
    int total = 1 << n;  // 2^n total meters
    printf("Pingala's Meters (Binary Patterns) for n=%d:\n", n);
    printf("Total: %d patterns\n\n", total);
    
    for (int i = 0; i < total; i++) {
        printf("  Meter %2d: ", i);
        // Pingala's right-to-left representation
        for (int j = n-1; j >= 0; j--) {
            printf("%c", (i >> j) & 1 ? 'G' : 'L');  // Guru/Laghu
        }
        printf("  (0x%0*X)\n", (n+3)/4, i);
    }
}

// Pingala's Meru Prastara (Pascal's Triangle) - combinatorial count
// Used in modern AI for:
// - Network architecture search
// - Weight initialization patterns
// - Dropout mask generation
void pingala_meru_prastara(int rows) {
    printf("\nPingala's Meru Prastara (Pascal's Triangle):\n");
    printf("Used for combinatorial counting in architecture search\n\n");
    
    int triangle[20][20] = {0};
    
    for (int i = 0; i < rows; i++) {
        triangle[i][0] = 1;
        triangle[i][i] = 1;
        
        for (int j = 1; j < i; j++) {
            triangle[i][j] = triangle[i-1][j-1] + triangle[i-1][j];
        }
        
        // Print row
        for (int s = 0; s < rows - i; s++) printf("  ");
        for (int j = 0; j <= i; j++) {
            printf("%4d", triangle[i][j]);
        }
        printf("\n");
    }
}

// Pingala's algorithm for finding nCr (combinations)
// Directly used in: attention head selection, mixture-of-experts routing
uint64_t pingala_nCr(int n, int r) {
    if (r > n) return 0;
    if (r == 0 || r == n) return 1;
    
    // Pingala's method: iterative multiplication-division
    uint64_t result = 1;
    for (int i = 1; i <= r; i++) {
        result = result * (n - r + i) / i;
    }
    return result;
}

int main() {
    printf("╔══════════════════════════════════════════════════╗\n");
    printf("║   PINGALA'S ALGORITHMS (Chandas Shastra)        ║\n");
    printf("║   ~300 BCE - First Binary System                ║\n");
    printf("╚══════════════════════════════════════════════════╝\n\n");
    
    // 1. Binary enumeration
    pingala_meters(4);
    
    // 2. Meru Prastara (Pascal's Triangle)
    pingala_meru_prastara(8);
    
    // 3. Combinatorial selection
    printf("\nPingala's nCr (Attention Head Selection):\n");
    int n = 14;  // Like 14 attention heads
    for (int r = 0; r <= n; r += 2) {
        printf("  C(%2d, %2d) = %10lu\n", n, r, pingala_nCr(n, r));
    }
    
    printf("\n✅ These map directly to:\n");
    printf("  • Neural architecture search (all patterns)\n");
    printf("  • Attention head selection (nCr)\n");
    printf("  • Beam search initialization (binary enumeration)\n");
    printf("  • Dropout mask generation (random meter selection)\n");
    
    return 0;
}