patrate2.cpp: In function 'int main()': patrate2.cpp:37: warning: unused variable 'L' patrate2.cpp:37: warning: unused variable 'start' patrate2.cpp:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result patrate2.cpp:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result patrate2.cpp:38: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result patrate2.cpp:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result patrate2.cpp:37: warning: 'ci' may be used uninitialized in this function