// 1405. Longest Happy String #include "leetcode.h" /* * a string 's' is called happy if it satisfies the following conditions: 's' * only contains the letters 'a', 'b', 'c', does not contain any of 'aaa', * 'bbb', or 'ccc' as a substring, contains at most 'n' occurences of the * letters 'a', 'b', 'c'. given three integers, return the longest possible * happy string. if there are multiple longest happy strings, return any of * them. if there is no such string, return the empty string */ class Solution { public: string longestDiverseString(int a, int b, int c, char aa = 'a', char bb = 'b', char cc = 'c') { if (a < b) return longestDiverseString(b, a, c, bb, aa, cc); if (b < c) return longestDiverseString(a, c, b, aa, cc, bb); if (!b) return string(min(2, a), aa); auto use_a = min(2, a), use_b = a - use_a >= b ? 1 : 0; return string(use_a, aa) + string(use_b, bb) + longestDiverseString(a - use_a, b - use_b, c, aa, bb, cc); } }; int main() { Solution obj; cout << obj.longestDiverseString(1, 1, 7) << endl; // expect: ccaccbcc cout << obj.longestDiverseString(7, 1, 0) << endl; // expect: aabaa }