Section 7: Loops

Types of Loops

• While
• Do while
• For
• For each

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Loop Flowcharts

1. While Loop

Entry Controlled Loop: Checks condition before execution.

graph TD
    Start((Start)) --> Cond{Condition}
    Cond -- True --> Proc[Process]
    Proc --> Cond
    Cond -- False --> End((End))

2. Do-While Loop

Exit Controlled Loop: Executes body at least once before checking condition.

graph TD
    Start((Start)) --> Proc[Process]
    Proc --> Cond{Condition}
    Cond -- True --> Proc
    Cond -- False --> End((End))

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Code Implementations

While Loop

int i = 0;
while (i < 10)
{
    cout << "Hello\n";
    i++;
}

Do-While Loop

int i = 0;
do
{
    cout << "Hello\n";
    i++;
} while(i < 10);

For Loop

for(int i = 0; i < 10; i++)
{
    cout << i << " Hello\n";
}

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Key Notes

• Counter-Controlled: The for loop is considered a counter-controlled loop.
  • Usually, a for loop is written with a counter i.
  • Example: for(int i=0; i<n; i++) where i is the counter.
• Infinite Loop: A for loop can be written with empty parameters to create an infinite loop:
  • for(;;)