Identifying errors

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Types of errors

There are two types of error you need to be familiar with:

Syntax errors: errors that break the rules of the programming language
Logic errors: errors that don't prevent the program running but cause unexpected output because they have been coded incorrectly

Identifying errors

You need to be able to identify the syntax and logic errors in programs. The pseudocode algorithm below totals all the numbers in the 0-indexed array scores.

Logic error: Line 2. Should start at 0 not 1 or else the first number in the array is not included.
Syntax error: Line 3. Square brackets are required to access elements of an array.

Trace table

A trace table is a method for helping to identify problems in an algorithm. It is a table that tracks the values of variables in a program as the program is executed.

Knowledge check

Questions:

Correct:

Question text

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