replace.cpp: In function 'void replace(char*, char*, char*)': replace.cpp:12: warning: unused variable 'poz' replace.cpp:7: warning: unused variable 'l2' replace.cpp:8: warning: unused variable 'v' replace.cpp:8: warning: unused variable 'aux' replace.cpp: In function 'int main()': replace.cpp:24: warning: unused variable 'cnt' replace.cpp:22: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result replace.cpp:23: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result replace.cpp:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result replace.cpp:28: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result replace.cpp:30: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result In file included from /usr/include/stdio.h:910, from /usr/include/c++/4.4/cstdio:45, from replace.cpp:1: In function 'char* gets(char*)', inlined from 'int main()' at replace.cpp:28: /usr/include/bits/stdio2.h:230: warning: call to '__gets_warn' declared with attribute warning: please use fgets or getline instead, gets can't specify buffer size /tmp/ccOJxVFO.o: In function `main': replace.cpp:(.text+0x13a): warning: the `gets' function is dangerous and should not be used. replace.cpp:(.text+0x158): warning: the `gets' function is dangerous and should not be used.