# UVa 944

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## 944 - Happy Numbers[edit]

## Summary[edit]

Read two positive integers between 1 and 99999 (inclusive) each; the first integer, L, is the low limit of the closed interval; the second one, H, is the high limit (L ≤ H). The output is composed of the happy numbers that lie in the interval [L,H], together with the number of iterations required for the corresponding sequences of squares to reach 1.

## Explanation[edit]

Instructions are clear. If you start with

If you reach 1 then is Happy else it's Unhappy!

## Gotcha's[edit]

- is unhappy when you meet a again and it means a loop, so it never meets 1.
- ``if is happy (unhappy), then any number in the sequence will also be happy (unhappy)
*, attention , if you know is happy (unhappy) don’t waste time and terminate it because the rest of sequence will be happy (unhappy).* - the number of iterations for ,if you meet a happy number in the sequence , simply add the size of current sequence to the number of iterations for , then = ( the number of iterations for ) - 1 and so on.

## Input[edit]

7 10 1 7 10 4 10 10 1 1 99970 99999

## Output[edit]

7 6 10 2 1 1 7 6 10 2 1 1 99971 7 99973 4 99978 8 99987 8