scor2.cpp: In function 'void dfs(int)': scor2.cpp:32: warning: comparison between signed and unsigned integer expressions scor2.cpp: In function 'int main()': scor2.cpp:80: warning: comparison between signed and unsigned integer expressions scor2.cpp:100: warning: comparison between signed and unsigned integer expressions scor2.cpp:115: warning: comparison between signed and unsigned integer expressions scor2.cpp:120: warning: comparison between signed and unsigned integer expressions scor2.cpp:49: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result scor2.cpp:50: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result scor2.cpp:53: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result scor2.cpp:57: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result /tmp/ccLynHBu.o: In function `main': scor2.cpp:(.text+0xb55): warning: the `gets' function is dangerous and should not be used.