Judge Information
./test.cpp: In function 'int main()':
./test.cpp:8:21: error: 'swap' was not declared in this scope
if(a<b){swap(a,b);}
^
./test.cpp:8:21: note: suggested alternatives:
In file included from /usr/include/c++/5/bits/quoted_string.h:38:0,
from /usr/include/c++/5/iomanip:45,
from ./test.cpp:3:
/usr/include/c++/5/sstream:783:5: note: 'std::__cxx11::swap'
swap(basic_stringbuf<_CharT, _Traits, _Allocator>& __x,
^
/usr/include/c++/5/sstream:804:5: note: 'std::__cxx11::swap'
swap(basic_stringstream<_CharT, _Traits, _Allocator>& __x,
^
In file included from /usr/include/c++/5/exception:162:0,
from /usr/include/c++/5/new:40,
from /usr/include/c++/5/ext/new_allocator.h:33,
from /usr/include/x86_64-linux-gnu/c++/5/bits/c++allocator.h:33,
from /usr/include/c++/5/bits/allocator.h:46,
from /usr/include/c++/5/string:41,
from /usr/include/c++/5/bits/locale_classes.h:40,
from /usr/include/c++/5/bits/ios_base.h:41,
from /usr/include/c++/5/iomanip:40,
from ./test.cpp:3:
/usr/include/c++/5/bits/exception_ptr.h:160:5: note: 'std::__exception_ptr::swap'
swap(exception_ptr& __lhs, exception_ptr& __rhs)
^
./test.cpp:7:25: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d %d",&a,&b);
^
./test.cpp:16:20: warning: ignoring return value of 'int system(const char*)', declared with attribute warn_unused_result [-Wunused-result]
system("pause");
^