Main.cc:3:10: error: ‘int y1’ redeclared as different kind of symbol
int n,x1,y1,x2,y2;
^~
In file included from /usr/include/features.h:424:0,
from /usr/include/x86_64-linux-gnu/c++/7/bits/os_defines.h:39,
from /usr/include/x86_64-linux-gnu/c++/7/bits/c++config.h:533,
from /usr/include/c++/7/cassert:43,
from /usr/include/x86_64-linux-gnu/c++/7/bits/stdc++.h:33,
from Main.cc:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:221:1: note: previous declaration ‘double y1(double)’
__MATHCALL (y1,, (_Mdouble_));
^
Main.cc: In function ‘int main()’:
Main.cc:8:12: error: expected primary-expression before ‘>’ token
cin>>x1>>>y1>>x2>>y2;
^
Main.cc:8:15: error: invalid operands of types ‘double(double) throw ()’ and ‘int’ to binary ‘operator>>’
cin>>x1>>>y1>>x2>>y2;
~~^~~~
Main.cc:10:14: error: invalid conversion from ‘double (*)(double) throw ()’ to ‘int’ [-fpermissive]
for(int k=y1;k<=y2;k++){
^~
Main.cc:15:2: error: ‘ans’ was not declared in this scope
ans=0;
^~~
Main.cc:15:2: note: suggested alternative: ‘abs’
ans=0;
^~~
abs