A flowchart is a diagram that depicts an algorithm.

Flowcharts use these symbols:
 

Diagram 1 shows a flowchart of an algorithm to add two numbers together.

Diagram 1

Diagram 2 shows a flowchart containing selection.

Diagram 2

Diagram 3 shows a flowchart containing iteration.

Diagram 3

The algorithm keeps asking the user for a password until they get it correct.

Diagram 4 shows a flowchart of an algorithm.

Diagram 4

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What does Diagram 4 do?

Finds and outputs the index of an item in a list, or -1 if not found.

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