Loops

While loop

# First Program
a = 10
while a <= 20:
    print(a)
    a += 1
else:
    print("Reached 20")
"""
Output:
10
11
12
13
14
15
16
17
18
19
20
Reached 20
"""

# Second Program
a = 10
while a <= 20:
    print(a)
    a += 1
    if a == 21:
        break
else:
    print("Reached 20")
"""
Output:
10
11
12
13
14
15
16
17
18
19
20
"""
# Single Statement while
b = 10
while b <= 20:
    print("b")
    b += 1

For Loop

for i in range(3):  # Prints 0 to 2
    print(i)
for j in range(0, 5):  # Prints 0 to 4
    print(j)
for k in range(0, 20, 5):  # Prints 0,5,10,15
    print(k)
for l in range(20, 0, -5):  # prints 20,15,10,5
    print(l)
# Else in for loop
# First Program
for i in range(5):
    print(i)
else:
    print("Reached 4")
# Second Program
for j in range(5):
    print(j)
    if j == 4:
        break
else:
    print("This is not executed")