biperm.cpp: In function 'int solve(int)': biperm.cpp:33: warning: comparison between signed and unsigned integer expressions biperm.cpp:45: warning: comparison between signed and unsigned integer expressions biperm.cpp: In function 'int main()': biperm.cpp:67: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result biperm.cpp:68: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result biperm.cpp:69: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result biperm.cpp:71: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result biperm.cpp:74: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result