Python break and
continue
What is the use of
break and continue in Python?
The break and continue statements In
Python, break and continue statements can alter the flow of a normal loop.
Loops iterate over a block of code until test expression is
false, but sometimes we wish to terminate the current iteration or even the
whole loop without checking test expression.
are used in these cases.
Python break statement
The break statement terminates the loop containing it. Control
of the program flows to the statement immediately after the body of the loop.
If break statement is inside a nested loop (loop inside another
loop), break will terminate the innermost loop.
Syntax of break
break
Example: Python break
# Use of break statement inside loop
for val in "string":
if val ==
"i":
break
print(val)
print("The end")
Output
s
t
r
The end
In this program, we iterate
through the "string" sequence. We check if the
letter is "i", upon which we break from the loop. Hence,
we see in our output that all the letters up till "i" gets
printed. After that, the loop terminates.
Example: Python break
for i in [1,2,3,4,5]:
if i==4:
print "Element found"
break
print i,
Output
1 2 3 Element found
Example: Python break
for letter in 'Python3':
if letter == 'o':
break
print (letter)
Output
P
y
t
h
Python continue statement
The continue statement is used to skip the rest of the code
inside a loop for the current iteration only. Loop does not terminate but
continues on with the next iteration.
Syntax of Continue
continue
Example: Python continue
#
Program to show the use of continue statement inside loops
for
val in "string":
if val == "i":
continue
print(val)
print("The
end")
Output
s
t
r
n
g
The end
This program is same as the above example
except the break statement has been replaced with continue.
We continue with the
loop, if the string is
"i", not executing the rest
of the block. Hence, we see in our output that all the letters except "i" gets printed.
Example: Python continue
a=0
while a<=5:
a=a+1
if a%2==0:
continue
print a
print "End of Loop"
Output
1
3
5
End of Loop
Python pass statement
What is pass statement in Python?
In Python programming,
pass is a null
statement. The difference between a comment and pass statement in Python is that, while
the interpreter ignores a comment entirely, pass is not ignored.
However,
nothing happens when pass is executed. It results into no operation (NOP).
Syntax of pass
pass
We generally use it as a placeholder.
Suppose we have a loop or a function that is not implemented yet, but we want to implement it
in the future. They cannot have an empty body. The interpreter would complain.
So, we use the
pass statement to
construct a body that does nothing.
Example: pass Statement
# pass is just a placeholder for
# functionality to be added later.
sequence = {'p', 'a', 's', 's'}
for val in sequence:
pass
We can do the same thing in an empty function or class as
well.
def function(args):
pass
class example:
pass
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