The challenge

Given an integer as input, can you round it to the next (meaning, “higher”) multiple of 5?

Examples:

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input:    output:
0    ->   0
2    ->   5
3    ->   5
12   ->   15
21   ->   25
30   ->   30
-2   ->   0
-5   ->   -5
etc.

Input may be any positive or negative integer (including 0).

You can assume that all inputs are valid integers.

The solution in Python code

Option 1:

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def round_to_next5(n):
    return n + (5 - n) % 5

Option 2:

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def round_to_next5(n):
    while n%5!=0:
        n+=1
    return n

Option 3:

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import math
def round_to_next5(n):
    return math.ceil(n/5.0) * 5

Test cases to validate our solution

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inp = 0
out = round_to_next5(inp)
test.assert_equals(out, 0, "Input: {}".format(inp))

inp = 1
out = round_to_next5(inp)
test.assert_equals(out, 5, "Input: {}".format(inp))

inp = -1
out = round_to_next5(inp)
test.assert_equals(out, 0, "Input: {}".format(inp))

inp = 5
out = round_to_next5(inp)
test.assert_equals(out, 5, "Input: {}".format(inp))

inp = 7
out = round_to_next5(inp)
test.assert_equals(out, 10, "Input: {}".format(inp))

inp = 20
out = round_to_next5(inp)
test.assert_equals(out, 20, "Input: {}".format(inp))

inp = 39
out = round_to_next5(inp)
test.assert_equals(out, 40, "Input: {}".format(inp))