Compilare: user.cpp: In function ‘int main()’: user.cpp:30:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rj.in","r",stdin); ^ user.cpp:31:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rj.out","w",stdout); ^ user.cpp:33:28: 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:37:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &c); ^ user.cpp:43:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^ user.cpp:56:33: warning: ‘xy’ may be used uninitialized in this function [-Wmaybe-uninitialized] cout<<tmin<<" "<<xt<<" "<<xy; ^ user.cpp:56:22: warning: ‘xt’ may be used uninitialized in this function [-Wmaybe-uninitialized] cout<<tmin<<" "<<xt<<" "<<xy; ^