Compilare: user.cpp: In function ‘int main()’: user.cpp:172:17: warning: variable ‘L’ set but not used [-Wunused-but-set-variable] int L, R, old; ^ user.cpp:194:13: warning: variable ‘L’ set but not used [-Wunused-but-set-variable] int L, R, old; ^ user.cpp: In function ‘void read_and_normalize()’: user.cpp:28:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d\n", &N, &M); ^ user.cpp:29:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (sir + 1); ^ user.cpp:38:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (sir + 1); ^ user.cpp: In function ‘int main()’: user.cpp:107:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("compunere.in", "r", stdin); ^ user.cpp:108:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("compunere.out", "w", stdout); ^ /tmp/ccPm8Bxj.o: In function `read_and_normalize()': user.cpp:(.text+0x272): warning: the `gets' function is dangerous and should not be used.