## randint() Function in Python

** randint()** is an inbuilt function of the

*random module*in Python3. The random module gives access to various useful functions and one of them being able to generate random numbers, which is

*randint()*.

**Syntax :**

randint(start, end)

**Parameters :**

(start, end) :Both of them must be integer type values.

**Returns :**

A random integer in range [start, end] including the end points.

**Errors and Exceptions :**

ValueError :Returns a ValueError when floating point values are passed as parameters.TypeError :Returns a TypeError when anything other than numeric values are passed as parameters.

**Code #1 :**

`# Python3 program explaining work` `# of randint() function` ` ` `# imports random module` `import` `random` ` ` `# Generates a random number between` `# a given positive range` `r1 ` `=` `random.randint(` `0` `, ` `10` `)` `print` `(` `"Random number between 0 and 10 is % s"` `%` `(r1))` ` ` `# Generates a random number between ` `# two given negative range` `r2 ` `=` `random.randint(` `-` `10` `, ` `-` `1` `)` `print` `(` `"Random number between -10 and -1 is % d"` `%` `(r2))` ` ` `# Generates a random number between ` `# a positive and a negative range` `r3 ` `=` `random.randint(` `-` `5` `, ` `5` `)` `print` `(` `"Random number between -5 and 5 is % d"` `%` `(r3))` |

**Output :**

Random number between 0 and 10 is 5 Random number between -10 and -1 is -7 Random number between -5 and 5 is 2

**Code #2 :** Program demonstrating the ValueError.

`# imports random module` `import` `random` ` ` `'''If we pass floating point values as` `parameters in the randint() function'''` ` ` `r1 ` `=` `random.randint(` `1.23` `, ` `9.34` `)` `print` `(r1)` |

**Output :**

Traceback (most recent call last): File "/home/f813370b9ea61dd5d55d7dadc8ed5171.py", line 6, in r1=random.randint(1.23, 9.34) File "/usr/lib/python3.5/random.py", line 218, in randint return self.randrange(a, b+1) File "/usr/lib/python3.5/random.py", line 182, in randrange raise ValueError("non-integer arg 1 for randrange()") ValueError: non-integer arg 1 for randrange()

**Code #3 :** Program demonstrating the TypeError.

`# imports random` `import` `random` ` ` `'''If we pass string or character literals as` `parameters in the randint() function'''` ` ` `r2 ` `=` `random.randint(` `'a'` `, ` `'z'` `)` `print` `(r2)` |

**Output :**

Traceback (most recent call last): File "/home/fb805b21fea0e29c6a65f62b99998953.py", line 5, in r2=random.randint('a', 'z') File "/usr/lib/python3.5/random.py", line 218, in randint return self.randrange(a, b+1) TypeError: Can't convert 'int' object to str implicitly

**Applications :**

The randint() function can be used to simulate a lucky draw situation.

Let’s say User has participated in a lucky draw competition. The user gets three chances to guess the number between 1 and 10. If guess is correct user wins, else loses the competition.

`# importing randint function` `# from random module` `from` `random ` `import` `randint` ` ` `# Function which generates a new ` `# random number everytime it executes` `def` `generator():` ` ` `return` `randint(` `1` `, ` `10` `)` ` ` `# Function takes user input and returns` `# true or false depending whether the` `# user wins the lucky draw!` `def` `rand_guess():` ` ` ` ` `# calls generator() which returns a` ` ` `# random integer between 1 and 10` ` ` `random_number ` `=` `generator()` ` ` ` ` `# defining the number of` ` ` `# guesses the user gets` ` ` `guess_left ` `=` `3` ` ` ` ` `# Setting a flag variable to check` ` ` `# the win-condition for user` ` ` `flag ` `=` `0` ` ` ` ` `# looping the number of times` ` ` `# the user gets chances` ` ` `while` `guess_left > ` `0` `:` ` ` ` ` `# Taking a input from the user` ` ` `guess ` `=` `int` `(` `input` `(` `"Pick your number to "` ` ` `"enter the lucky draw\n"` `))` ` ` ` ` `# checking whether user's guess` ` ` `# matches the generated win-condition` ` ` `if` `guess ` `=` `=` `random_number:` ` ` ` ` `# setting flag as 1 if user guessses ` ` ` `# correctly and then loop is broken` ` ` `flag ` `=` `1` ` ` `break` ` ` ` ` `else` `:` ` ` ` ` `# If user's choice doesn't match` ` ` `# win-condition then it is printed` ` ` `print` `(` `"Wrong Guess!!"` `)` ` ` ` ` `# Decrementing number of ` ` ` `# guesses left by 1 ` ` ` `guess_left ` `-` `=` `1` ` ` ` ` `# If win-condition is satisfied then,` ` ` `# the function rand_guess returns True` ` ` `if` `flag ` `is` `1` `:` ` ` `return` `True` ` ` ` ` `# Else the function returns False` ` ` `else` `:` ` ` `return` `False` ` ` `# Driver code` `if` `__name__ ` `=` `=` `'__main__'` `:` ` ` `if` `rand_guess() ` `is` `True` `:` ` ` `print` `(` `"Congrats!! You Win."` `)` ` ` `else` `:` ` ` `print` `(` `"Sorry, You Lost!"` `)` |

**Output :**

Pick your number to enter the lucky draw 8 Wrong Guess!! Pick your number to enter the lucky draw 9 Wrong Guess!! Pick your number to enter the lucky draw 0 Congrats!! You Win.

Last Updated on October 25, 2021 by admin