Compilare: user.cpp: In function ‘int main()’: user.cpp:34: warning: format ‘%u’ expects type ‘unsigned int’, but argument 2 has type ‘long unsigned int’ user.cpp:9: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:10: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:14: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:17: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result user.cpp:12: warning: ‘sol’ may be used uninitialized in this function /tmp/ccM1coli.o: In function `main': user.cpp:(.text+0xac): warning: the `gets' function is dangerous and should not be used.