#include <stdio.h>

int main() {
    printf("Hello!\n");
    return 0;
}

int age = 25;
float price = 19.99;
char grade = 'A';
const int MAX = 100;

if (x > 0) {
    // positive
} else if (x < 0) {
    // negative
} else {
    // zero
}

switch (choice) {
    case 1: break;
    case 2: break;
    default: break;
}

for (int i = 0; i < n; i++) {
    // code
}

while (condition) {
    // code
}

int add(int a, int b) {
    return a + b;
}

int arr[5] = {1, 2, 3};
char str[] = "Hello";

int x = 10;
int *ptr = &x;
printf("%d", *ptr);

struct Point {
    int x, y;
};
struct Point p = {1, 2};

int *arr = malloc(n * sizeof(int));
if (arr) {
    free(arr);
}

FILE *f = fopen("file.txt", "r");
if (f) {
    fclose(f);
}