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Write a one line C function to round floating point numbers
• Difficulty Level : Easy
• Last Updated : 02 Jun, 2017

Algorithm: roundNo(num)
1. If num is positive then add 0.5.
2. Else subtract 0.5.
3. Type cast the result to int and return.

Example:
num = 1.67, (int) num + 0.5 = (int)2.17 = 2
num = -1.67, (int) num – 0.5 = -(int)2.17 = -2

Implementation:

 `/* Program for rounding floating point numbers */``# include`` ` `int` `roundNo(``float` `num)``{``    ``return` `num < 0 ? num - 0.5 : num + 0.5;``}`` ` `int` `main()``{``    ``printf``(``"%d"``, roundNo(-1.777));``    ``getchar``();``    ``return` `0;``}`

Output: -2

Time complexity: O(1)
Space complexity: O(1)

Now try rounding for a given precision. i.e., if given precision is 2 then function should return 1.63 for 1.63322 and -1.63 for 1.6332.

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