Compilare: user.cpp: In function ‘int main()’: user.cpp:18:19: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[100]’ [-Wformat=] scanf("%s", &v); ^ user.cpp:27:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(v); i++) { ^ user.cpp:16:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("abc2.in", "r", stdin); ^ user.cpp:17:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("abc2.out", "w", stdout); ^ user.cpp:18:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", &v); ^ user.cpp:22:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", cuv); ^