Find smallest N for 5-and-21 sums
Problem Description
You are given two positive integers, 5 and 21. A positive integer x is defined as representable if it can be expressed in the form x = 5a + 21b, where a and b are non-negative integers.
For example, 99 is representable because it can be written as 4 * 21 + 3 * 5 = 84 + 15 = 99.
Your task is to find the smallest integer N such that every integer greater than or equal to N is representable.
Output this minimal value of N.
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Find smallest N for 5-and-21 sums
Problem Description
You are given two positive integers, 5 and 21. A positive integer x is defined as representable if it can be expressed in the form x = 5a + 21b, where a and b are non-negative integers.
For example, 99 is representable because it can be written as 4 * 21 + 3 * 5 = 84 + 15 = 99.
Your task is to find the smallest integer N such that every integer greater than or equal to N is representable.
Output this minimal value of N.