Compilare: user.cpp: In function ‘void read()’: user.cpp:20:27: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[20005]’ [-Wformat=] scanf("%s\n%s", &a, &b); ^ user.cpp:20:27: warning: format ‘%s’ expects argument of type ‘char*’, but argument 3 has type ‘char (*)[20005]’ [-Wformat=] user.cpp:19:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d", &N, &M, &K); ^ user.cpp:20:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s\n%s", &a, &b); ^ user.cpp: In function ‘int main()’: user.cpp:41:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("edist.in", "r", stdin); ^ user.cpp:42:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("edist.out", "w", stdout); ^