## Conditionals¶

Let us go through conditionals in Python. We typically use “if else” for conditionals. Let us perform a few tasks to understand how conditionals are developed.* Create a variable i with 5. Write a conditional to print whether i is even or odd.

In [1]:

```
i = 5
```

In [2]:

```
# Regular if else
if i % 2 == 0:
print("even")
else:
print("odd")
```

odd

In [3]:

```
# (cond) ? on_true : on_false
```

In [4]:

```
# on_true (cond) else on_false
```

In [5]:

```
# Ternary Operator (one liner)
print("even") if i % 2 == 0 else print("odd")
```

odd

- Improvise it to check if i is 0 and print zero

In [7]:

```
i = int(input("Enter an integer: "))
```

In [8]:

```
if i == 0:
print(f"i is 0")
elif i % 2 == 0:
print(f"{i} is even")
else:
print(f"{i} is odd")
```

45 is odd

- Object of type
`None`

is special object which represent nothing. At times we need to check against`None`

.

In [9]:

```
n = None
print('Not None') if n else print(n)
```

None

In [10]:

```
i = int(input("Enter an integer: "))
```

In [11]:

```
if i:
print('Not None')
else: print(n)
```

Not None

In [13]:

```
i = int(input("Enter an integer: "))
```

In [14]:

```
if not i % 2 == 0: print(f'{i} is odd')
```

47 is odd

- We can also perform boolean operations such as
**boolean or**and**boolean and**.

### Task 1¶

Determine the category of the baby.

- Print
**New Born or Infant**till 6 months. - Print
**Toddler**from 7 months to 18 months. - Print
**Grown up**from 19 months to 144 months. - Print
**Youth**from 145 months to 216 months

In [15]:

```
age = int(input('Enter age in months: '))
```

In [16]:

```
if age <= 6:
print('New Born or Infant')
elif age > 6 and age <= 18:
print('Toddler')
elif age > 18 and age <= 144:
print('Grown up')
elif age > 144 and age <= 216:
print('Youth')
else:
print('Adult')
```

Adult

### Task 2¶

Check if the number is even or divisible by 3.

In [17]:

```
n = int(input('Enter integer: '))
```

In [18]:

```
if n % 2 == 0 or n % 3 == 0:
print(f'Number {n} is even or divisible by 3')
```

Number 18 is even or divisible by 3

### Task 3¶

Check if the number is even and divisible by 3

In [19]:

```
n = int(input('Enter integer: '))
```

In [20]:

```
if n % 2 == 0 and n % 3 == 0:
print(f'Number {n} is even and divisible by 3')
elif n % 3 == 0:
print(f'Number {n} is divisible by 3 but not even')
elif n % 2 == 0:
print(f'Number {n} is even but not divisible by 3')
```

Number 86 is even but not divisible by 3