Compilare: user.cpp: In function ‘int main()’: user.cpp:72:22: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[15]’ [-Wformat=] scanf("%s\n", &first); ^ user.cpp:73:16: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[800005]’ [-Wformat=] scanf("%s", &s); ^ user.cpp:77:34: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 2 has type ‘std::unordered_map<int, int>::mapped_type {aka int}’ [-Wformat=] printf("%lld\n", m[nr(first, 0)]); ^ user.cpp:84:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < strlen(s); i += p) { ~~^~~~~~~~~~~ user.cpp:68:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("decod.in", "r", stdin); ^ user.cpp:69:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("decod.out", "w", stdout); ^ user.cpp:71:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &k, &p); ^ user.cpp:72:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s\n", &first); ^ user.cpp:73:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", &s); ^