Compilare: user.cpp: In function ‘void solve()’: user.cpp:107:30: warning: format ‘%s’ expects argument of type ‘char*’, but argument 2 has type ‘char (*)[9]’ [-Wformat=] scanf("%s %s", &s, &t); ^ user.cpp:107:30: warning: format ‘%s’ expects argument of type ‘char*’, but argument 3 has type ‘char (*)[9]’ [-Wformat=] user.cpp: In function ‘void read()’: user.cpp:89:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("eliminare.in", "r", stdin); ^ user.cpp:90:29: 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:93:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(s); ^ user.cpp: In function ‘void solve()’: user.cpp:107:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s %s", &s, &t); ^ user.cpp: In function ‘void write()’: user.cpp:136:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("eliminare.out", "w", stdout); ^ /tmp/cc5u5KUv.o: In function `read()': user.cpp:(.text+0x2f8): warning: the `gets' function is dangerous and should not be used.