#include <stdio.h>
#include <stdlib.h>

#define MAX_INPUT 100

typedef struct {
    int line_number;
    int value;
} Input;

typedef struct{
    int line_number;
    int doubled_value;
} IntermediateInput;

typedef struct {
    int doubled_value;
    int line_numbers[MAX_INPUT];
    int count;
} Output;

void map(Input* input, IntermediateInput* intermediate_input);
void groupByKey(IntermediateInput* input, Output *output, int *result_count);
void reduce(Output* output);

int main() {
    Input input_data[MAX_INPUT];
    int input_size = 0;
    int value;

    // Read input values until "end" is encountered
    printf("Enter values (one per line). Type 'end' to finish:\n");
    while (input_size < MAX_INPUT) {
        char buffer[100];
        if (fgets(buffer, sizeof(buffer), stdin) == NULL) {
            break;
        }
        if (sscanf(buffer, "%d", &value) == 1) {
            input_data[input_size].line_number = input_size + 1;
            input_data[input_size].value = value;
            input_size++;
        } else if (sscanf(buffer, "end") == 0) {
            break;
        } else {
            printf("Invalid input. Please enter an integer or 'end' to finish.\n");
        }
    }

    // Step 1: Map phase
    
    IntermediateInput mapped_results[MAX_INPUT] = {0};

    for (int i = 0; i < input_size; i++) {
        map(&input_data[i], &mapped_results[i]);
    }

    // Step 2: Grouping phase
    
    Output output_results[MAX_INPUT] = {0};
    int result_count = 0;

    for (int i = 0; i < input_size; i++) {
        groupByKey(&mapped_results[i], output_results, &result_count);
    }

    // Step 3: Reduce phase
    for (int i = 0; i < result_count; i++) {
        if (output_results[i].count > 0) {
            reduce(&output_results[i]);
        }
    }

    return 0;
}

void map(Input* input, IntermediateInput *intermediate_input) { 
    // TODO:
    // Double the value of the input
}

void groupByKey(IntermediateInput* input, Output *output, int *result_count){
    // TODO:
    // Group entries
    // If the doubled value exists in the output entries, add it to the output's line_numbers list
    // If it doesn't exist, add a new entry to the output
}

void reduce(Output* output) {
    // TODO:
    // Print the doubled number and line numbers
}