Page 281 - Computer_Science_F5

Computer Science Table 4.13 shows the difference between while...loop and do-while...loop
statements.

Table 4.13: Difference between while...loop statements and do-while…..loop statements

While loop
Do-while loop
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Test the condition before execution; Body execution takes place once before
if the condition is true, the execution testing the condition. Then, if the
continues until the condition becomes condition is true, the execution continues
false. otherwise, the execution stops.
Testing of the loop body occurs at the Testing of the loop body occurs at the
top. bottom.
The loop stops execution if the condition Loop is executed at least once even
is false. though the condition is false

For loop Table 4.14: Body parts of ‘for….loop’
For loop is a predetermined type of loop. Part Function
It allows a user to enter the required Initialisation It initialises a variable
number of iterations to be done before counter
looping. For example, the program will Condition It tests the loop condition
prompt a teacher to enter the number of Increment/ It provides an increment
students before calculating their average decrement or decrement variable
marks to prepare the number of iterations. counter.
For loop contain variables that control
how many times the loop execution can Figure 4.50 shows the execution flowchart
occur. Unlike other control structures, of the for loop.
for...loop contains three body features:
initialisation, condition, and increment/
decrement counter. The syntax of for… Initialization
loop is given as : Increment/
Decrement
for (initialisation; condition ;

increment/decrement counter) Loop body
{ Condition True
loop body
} False
Table 4.14 shows the function of each
body part of the for…loop Figure 4.50: A flowchart of “for loop”

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for Advanced Secondary Schools

Computer Science Form 5.indd 272 23/07/2024 12:34