Compilare: user.cpp: In function ‘void read()’: user.cpp:10:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("charlie.in", "r", stdin); ^ user.cpp:11:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("charlie.out", "w", stdout); ^ user.cpp:12:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &p); ^ user.cpp:13:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp: In function ‘void task1()’: user.cpp:30:19: warning: ‘L’ may be used uninitialized in this function [-Wmaybe-uninitialized] L += 2; ^ /tmp/cc4zQvBE.o: In function `read()': user.cpp:(.text+0x61): warning: the `gets' function is dangerous and should not be used.