{"id":759,"date":"2024-10-19T13:33:54","date_gmt":"2024-10-19T08:03:54","guid":{"rendered":"https:\/\/codexplained.in\/?p=759"},"modified":"2025-11-24T15:37:15","modified_gmt":"2025-11-24T10:07:15","slug":"check-leap-year","status":"publish","type":"post","link":"https:\/\/codexplained.in\/?p=759","title":{"rendered":"Check Leap Year"},"content":{"rendered":"
\n#include <stdio.h>\n\nint main() \n{\n    int year;\n\n    \/\/ Asking the user to input a year\n    printf("Enter a year: ");\n    scanf("%d", &year);\n\n    \/\/ Leap year condition\n    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {\n        printf("%d is a leap year.\\n", year);\n    } else {\n        printf("%d is not a leap year.\\n", year);\n    }\n\n    return 0;\n}\n\n<\/pre><\/div>\n\n\n
Explanation:<\/h2>\n\n\n\n
Returning 0<\/strong>: We return 0<\/code> at the end of the program to indicate that the program has finished executing successfully.cCopy codereturn 0;<\/code><\/p>\n\n\n\n
Including the standard input-output library<\/strong>: We include the stdio.h<\/code> header file so that we can use printf<\/code> for displaying output and scanf<\/code> for taking input from the user.cCopy code#include <stdio.h><\/code><\/p>\n\n\n\n
Main function<\/strong>: The program execution starts from the main()<\/code> function.cCopy codeint main() { ... }<\/code><\/p>\n\n\n\n
Declaring a variable<\/strong>: We declare an integer variable year<\/code> to store the year that the user will input.cCopy codeint year;<\/code><\/p>\n\n\n\n
User input<\/strong>: We use printf<\/code> to prompt the user to enter a year and then use scanf<\/code> to capture that year and store it in the variable year<\/code>.cCopy codeprintf(\"Enter a year: \"); scanf(\"%d\", &year);<\/code><\/p>\n\n\n\n
Checking for a leap year<\/strong>:
  • A leap year occurs:
    • If a year is divisible by 4 but not<\/strong> divisible by 100, or<\/strong><\/li>
    • If a year is divisible by 400.<\/li><\/ul><\/li>
    • This means:
      • Years like 1996, 2004, and 2020 are leap years because they are divisible by 4 and not by 100.<\/li>
      • Years like 1900 are not<\/strong> leap years because they are divisible by 100 but not<\/strong> by 400.<\/li>
      • However, years like 2000 are leap years because they are divisible by 400.<\/li><\/ul><\/li>
      • The condition ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))<\/code> handles this logic.<\/li><\/ul>cCopy codeif ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) { printf(\"%d is a leap year.\\n\", year); } else { printf(\"%d is not a leap year.\\n\", year); }<\/code><\/p>\n\n\n\n
        Output<\/h2>\n\n\n\n
        Enter a year: 2020
        2020 is a leap year.<\/p>\n