// 2264. Largest 3-Same-Digit Number in String #include "leetcode.h" #include #include /* * given a string 'num' representing a large integer, an integer is good if it * meets the following conditions: if it is a substring of 'num' with length * '3', it consists of only one unique digit. return the maximum good integer as * a string or an empty string "" if no such integer. */ char *largestGoodInteger(char *num) { static char *patterns[] = {"999", "888", "777", "666", "555", "444", "333", "222", "111", "000"}; for (int i = 0; i < 10; i++) if (strstr(num, patterns[i])) return patterns[i]; return ""; } int main() { char *n1 = "6777133339", *lgi1 = largestGoodInteger(n1); char *n2 = "2300019", *lgi2 = largestGoodInteger(n2); char *n3 = "42352338", *lgi3 = largestGoodInteger(n3); printf("%s\n", lgi1); // expect: 777 printf("%s\n", lgi2); // expect: 000 printf("%s\n", lgi3); // expect: NULL }