aranjare1.cpp: In function 'std::pair<int, int> FrqCode()': aranjare1.cpp:54: warning: extended initializer lists only available with -std=c++0x or -std=gnu++0x aranjare1.cpp: In function 'int main()': aranjare1.cpp:71: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result aranjare1.cpp:75: warning: ignoring return value of 'char* gets(char*)', declared with attribute warn_unused_result aranjare1.cpp:93: 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 /usr/include/c++/4.4/i486-linux-gnu/bits/stdc++.h:45, from aranjare1.cpp:1: In function 'char* gets(char*)', inlined from 'int main()' at aranjare1.cpp:75: /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/ccxqqBEM.o: In function `main': aranjare1.cpp:(.text+0x41b): warning: the `gets' function is dangerous and should not be used. aranjare1.cpp:(.text+0x5af): warning: the `gets' function is dangerous and should not be used.