For Loop

For loop sets initial value for variable, condition and modification in one line.

Syntax

for varName in range(start, end, step): # Loop's body.

varName is initalized with value of start.

The loop repeats until varName reaches value of end .

Each iteration adds step value to varName.

step is optional parameter. If not specified the step of the loop is 1.

Examples

Let's have a program that prints each number from 1 to 10.

for x in range(1, 11): print(x)

Output:

1 2 3 4 5 6 7 8 9 10

x is initialized as 1.

The loop ends when x reaches value of 11.

Each iteration of the loop increments x by 1 since no step is specified.

Let's proceed with a program that prints each number in the range 0 - 50 that is divided by 5:

for x in range(0, 51, 5): print(x)

Output:

0 5 10 15 20 25 30 35 40 45 50

The last parameter of range specifies the step of the loop.

If we replace 51 with 50, then the last printed number will be 45.