Compilare: user.cpp: In function ‘bool solve()’: user.cpp:30:18: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[50000]’ [-Wformat=] scanf("%s",&a); ^ user.cpp:31:18: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[50000]’ [-Wformat=] scanf("%s",&b); ^ user.cpp:30:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",&a); ^ user.cpp:31:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s",&b); ^ user.cpp: In function ‘int main()’: user.cpp:79:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("twosets.in","r",stdin); ^ user.cpp:80:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:81:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c",&c); ^