In Python:
- Any non-zero and non-null values are considered as TRUE, and
- Zero or NULL are considered as FALSE value
Python has 3 types of decision/if-else statements as:
Statement | Description | Syntax |
---|---|---|
if | An if statement consists of a boolean expression followed by one or more statements. Ex:Boolean expression: (x>y) |
if expression: statement(s) |
if…else | An if statement can be followed by an optional else statement, which executes when the boolean expression (if condition) is FALSE. |
if expression: statement(s) else: statement(s) |
nested if | if or else if statement can be used inside another if or else if statement(s). |
if expression1: statement(s) if expression2: statement(s) elif expression3: statement(s) else: statement(s) else: statement(s) |
Ex (nested if-else):
x = 12 if x < 20: print "Expression value is < 20" if x == 14: print "and = 14" elif x == 12: print "and = 12" elif x == 10: print "and = 10" elif x < 10: print "Expression value is < 10" else: print "True expression not found" print "Tata!"
OUTPUT:
Expression value is < 20 and = 12 Tata!