Compilare: user.cpp: In function ‘int main()’: user.cpp:67:30: warning: value computed is not used [-Wunused-value] semn[++top2] == '('; ^ user.cpp:150:39: warning: format ‘%lf’ expects argument of type ‘double’, but argument 2 has type ‘int’ [-Wformat=] else printf("x = %lf\n", b / a); ^ user.cpp:40:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("date.in", "r", stdin); ^ user.cpp:41:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("date.out", "w", stdout); ^ user.cpp:144:33: warning: ‘b1’ may be used uninitialized in this function [-Wmaybe-uninitialized] a = a1 - a2; b = b1 - b2; ^ user.cpp:144:20: warning: ‘a1’ may be used uninitialized in this function [-Wmaybe-uninitialized] a = a1 - a2; b = b1 - b2; ^ /tmp/cclKqnS1.o: In function `main': user.cpp:(.text.startup+0x5e): warning: the `gets' function is dangerous and should not be used.