prasath M

 

Decision Making in Python (with Diagram) 

In Python, decision making allows a program to choose different actions based on conditions. The program evaluates a condition and decides which block of code should execute.

Decision making is done using conditional statements like if, if-else, and if-elif-else.

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if Statement

The if statement executes a block of code only when the condition is True.

Syntax

if condition:
    statement

Example

x = 10
if x > 5:
    print("x is greater than 5")

Diagram (Flowchart)

        Start
          |
      Condition
          |
     +----+----+
     |         |
   True      False
     |         |
 Execute     Skip
 Statement   Statement
     |
    End

---

if – else Statement

The if-else statement is used when there are two possible outcomes.

Example

num = 7
if num % 2 == 0:
    print("Even Number")
else:
    print("Odd Number")

Diagram

        Start
          |
     Check Condition
          |
      +---+---+
      |       |
     True    False
      |       |
 Print Even  Print Odd
      |       |
       +-----+
          |
         End

---

if – elif – else Statement

Used when multiple conditions must be checked.

Example

marks = 80

if marks >= 90:
    print("Grade A")
elif marks >= 60:
    print("Grade B")
else:
    print("Grade C")

Diagram

        Start
          |
     marks >= 90 ?
        /   \
      Yes    No
      |       |
   Grade A  marks >= 60 ?
              /     \
            Yes      No
            |        |
         Grade B   Grade C
              |
             End

---

Summary Table

Decision Statement	Purpose
if	Executes when condition is true
if-else	Two-way decision
if-elif-else	Multiple conditions

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Conclusion:
Decision making helps Python programs control the flow of execution and perform different actions based on conditions.