Compilare: main.cpp: In function 'int Build(int, int, int)': main.cpp:31:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ main.cpp: In function 'int Cmp()': main.cpp:52:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(s1); i++) frecv[s1[i] - 'a']++; ~~^~~~~~~~~~~~ main.cpp:53:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(s2); i++) frecv1[s2[i] - 'a']++; ~~^~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:67:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(s2); i++){ ~~^~~~~~~~~~~~ main.cpp:75:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(s2); i++) ~~^~~~~~~~~~~~ main.cpp: In function 'int Update(int, int, int, int)': main.cpp:49:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ main.cpp: In function 'int main()': main.cpp:61:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("swap.in", "r", stdin); ^ main.cpp:62:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("swap.out", "w", stdout); ^ main.cpp:64:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%s%s", s1, s2); ^