An earlier attempt at writing a bubble sort algorithm to sort meteorological pressure readings in a telemetry system shown in the pseudo-code below had different code for lines 7 and 8.
1 pressure[0] ← 1013
2 pressure[1] ← 950
3 pressure[2] ← 850
4 pressure[3] ← 700
5 pressure[4] ← 500
6 pressure[5] ← 300
7 FOR i ← 0 TO 4
8 FOR j ← 0 TO 4
9 IF pressure[j + 1] > pressure[j] THEN
10 temp ← pressure[j]
11 pressure[j] ← pressure[j + 1]
12 pressure[j + 1] ← temp
13 ENDIF
14 ENDFOR
15 ENDFOR
Lines 7 and 8 of the pseudo-code were originally written as:
7 FOR i ← 0 TO 5
8 FOR j ← 0 TO 5
Explain why the algorithm would result in a runtime error when the value 5 was used instead of the value 4 on these two lines.
Practise AQA GCSE Computer Science Sorting algorithms with exam-style questions for GCSE Computer Science. 62 questions, matched to the AQA GCSE Computer Science (8525) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.