Compilare: user.cpp: In function ‘void apply(int)’: user.cpp:18:9: warning: unused variable ‘s’ [-Wunused-variable] int s; ^ user.cpp: In function ‘int main()’: user.cpp:54:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("carte.in", "r", stdin); ^ user.cpp:55:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("carte.out", "w", stdout); ^ user.cpp:57:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &tsk); ^ user.cpp:59:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(str + 1); ^ user.cpp:60:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d ", &m); ^ user.cpp:65:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(pat); ^ /tmp/ccSaRO3H.o: In function `main': user.cpp:(.text.startup+0x80): warning: the `gets' function is dangerous and should not be used.