cal.c

#include <stdio.h>
#include <time.h>
#include <string.h>

const char* MONTH_NAMES[] = {
    "January", "February", "March", "April",
    "May", "June", "July", "August",
    "September", "October", "November", "December"
};

int get_days_in_month(int month, int year) {
    int days[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    if (month == 1) { // February
        if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0)
            return 29;
    }
    return days[month];
}

int get_first_day_of_month(int month, int year) {
    struct tm time_info = {0};
    time_info.tm_year = year - 1900;
    time_info.tm_mon = month;
    time_info.tm_mday = 1;
    mktime(&time_info);
    return time_info.tm_wday;
}

void print_calendar(int month, int year) {
    // Print month name
    printf("%s %d\n", MONTH_NAMES[month], year);
    
    // Print weekday headers
    printf("M  T  W  T  F  S  S\n");
    
    int days = get_days_in_month(month, year);
    int first_day = get_first_day_of_month(month, year);
    if (first_day == 0) first_day = 7;  // Convert Sunday from 0 to 7
    
    // Print leading dots
    for (int i = 1; i < first_day; i++) {
        printf(".  ");
    }
    
    // Print days
    for (int day = 1; day <= days; day++) {
        printf("%2d ", day);
        if ((day + first_day - 1) % 7 == 0 || day == days)
            printf("\n");
    }
    
    // Print trailing dots to complete the last week if needed
    int last_day_position = (days + first_day - 1) % 7;
    if (last_day_position != 0) {
        for (int i = last_day_position; i < 7; i++) {
            printf(".  ");
        }
        printf("\n");
    }
}

int main() {
    // Using April 2025 as per the current date
    print_calendar(3, 2025);  // Month is 0-based (3 = April)
    return 0;
}