count_if

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

int count_if(void* base, size_t num, size_t size, int (*pred)(const void*)) {
    int count = 0;
    for (size_t i = 0; i < num; i++) {
        if (pred(base + i*size)) {
            count++;
        }
    }
    return count;
}

int is_even(const void* p) {
    if (*(int*)p % 2 == 0) {
        return 1;
    }
    return 0;
}

int is_even_double(const void* p) {
    double d = *(double*)p;
    int integer_part = (int)d;
    double fractional_part = d - integer_part;
    if (fractional_part < 1e-6 && integer_part % 2 == 0) {
        return 1;
    }
    return 0;
}

int main() {
    int size;
    scanf("%d", &size);
    void* arr = malloc(20*size);
    if (arr == NULL) {
        printf("Error: Memory allocation failed\n");
        return 1;
    }
    for (int i = 0; i < 5; i++) {
        if (size == 4) {
            scanf("%d", (int*)arr + i);
        } else if (size == 8) {
            scanf("%lf", (double*)arr + i);
        }
    }
    int count;
    if (size == 4) {
        count = count_if(arr, 5, size, is_even);
    } else if (size == 8) {
        count = count_if(arr, 5, size, is_even_double);
    }
    printf("Number of even elements: %d\n", count);
    free(arr);
    return 0;
}