Compilare: user.cpp: In function ‘int main()’: user.cpp:101:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < Ans.size(); ++ i) ^ user.cpp:65:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("partialmatch.in", "r", stdin); ^ user.cpp:66:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("partialmatch.out", "w", stdout); ^ user.cpp:68:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(S + 1); N = strlen(S + 1); ^ user.cpp:69:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(B + 1); Len = strlen(B + 1); ^ user.cpp:71:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%i", &K); ^ /tmp/ccCLXltU.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.