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KwickClips C · 42 sec · free

What is 5! ?

Short answer. 120.

What should a sum start at?

0.

Remember

Sum starts at 0
Product starts at 1

Your factorial program prints zero. What went wrong? F is the factorial. It must start at one, not zero. Zero times anything stays zero. Starting at one gives one hundred twenty. A sum starts at zero. A product starts at one.

This clip is from the full lesson: Loops in C: while, do-while and for — 7 minutes, with the tables, the quick answers and the whole lesson in text.

Useful for: CBSE Class 9 Information Technology (402), GSEB Std 10 Computer Studies

More KwickClips from this lesson

Table: while checks before, runs 0; for checks before, runs 0; do-while checks after, runs 1.Which loops are entry controlled?41 secC nested for loops printing *, **, *** on three lines.Which loop handles columns?41 secC for loop with continue at 3 and break at 5, printing 1 2 4.What does continue do?39 sec
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