Attempting to create multiple if-else conditions - c

Question

I am writing a program that involves checking the validity of a date. I have set the conditions for the months which have 31 days in them, and I have set the conditions for the months which have 30 days in them. I left out February because there are issues with leap year.
When I run the program, it is able to print "SUCCESS" on the screen for all valid dates. However, when I try to enter an invalid date, the program fails to write "FAILURE" on the screen, as I have it set to do [at least I believe].
What is wrong with the code here?
#include <stdio.h>
int main ()
{
int month = 1;
int day = 32;
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8
|| month == 10 || month == 12)
{
if (0 < day && day < 32)
{
return printf("%s","SUCCESS");
}
}
else if (month == 4 || month == 6 || month == 9 || month == 11)
{
if (0 < day && day < 31 )
{
return printf("%s","SUCCESS");
}
}
else
{
return printf("%s","FAILURE");
}
return 1;
}

Answer 1

Your code have a wrong flow and #JoshStir is right about it.
I may know when you enter in a conditional statement, the other conditionals in the same level are ignored.
You test guide your code to enter in your first condicional.
int month = 1;
int day = 32;
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8
|| month == 10 || month == 12)
{
//--> Flow pass through here ( cause month == 1 )
if (0 < day && day < 32)
{
//Flow DON'T pass through here ( cause day == 32)
return printf("%s","SUCCESS");
}
}
else if (month == 4 || month == 6 || month == 9 || month == 11)
{
//--> Flow DON'T pass through here ( cause flow ENTERER FIRST IF STATEMENT BEFORE)
if (0 < day && day < 31 )
{
return printf("%s","SUCCESS");
}
}
else
{
//--> Flow DON'T pass through here ( cause flow ENTERED FIRST IF STATEMENT BEFORE)
return printf("%s","FAILURE");
}
I advice you to review your code.
Try rethink and considerate what did #JoshStir advice you too.
Maybe using months and days in same comparation operation a good idea.

Answer 2

We were all new once, so I'll try to answer your question as clearly as I can. Given your test data:
int month = 1;
int day = 32;
your code will enter the first if statement (as month == 1)
if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8
|| month == 10 || month == 12)
It will then check against the inner if statement (is day > 0 and < 32?)
if (0 < day && day < 32)
day == 32, so it will not enter the if and print "SUCCESS", it will exit the if and then exit the application. If you want the data above to enter the failure condition, you would want something somewhat like the following:
if ((month == 1 || month == 3 || month == 5 || month == 7 || month == 8|| month == 10 || month == 12) && (day > 0 && day < 32))