grup.cpp: In function 'void read()': grup.cpp:37: warning: format '%s' expects type 'char*', but argument 2 has type 'char (*)[21]' grup.cpp:37: warning: format '%s' expects type 'char*', but argument 3 has type 'char (*)[21]' grup.cpp:34: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result grup.cpp:37: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result grup.cpp: In function 'void comb(int, int)': grup.cpp:119: warning: operation on 'k' may be undefined grup.cpp: In function 'int main()': grup.cpp:135: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result grup.cpp:136: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result