/in/foo.cc:10:19: error: 'int y1 [200]' redeclared as different kind of symbol
 int x1[200],y1[200],x2[200],y2[200];
                   ^
In file included from /usr/include/features.h:364:0,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/os_defines.h:39,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/c++config.h:507,
                 from /usr/include/c++/6/cassert:43,
                 from /usr/include/x86_64-linux-gnu/c++/6/bits/stdc++.h:33,
                 from /in/foo.cc:1:
/usr/include/x86_64-linux-gnu/bits/mathcalls.h:251:1: note: previous declaration 'double y1(double)'
 __MATHCALL (y1,, (_Mdouble_));
 ^
/in/foo.cc: In function 'int BFS(int, int)':
/in/foo.cc:28:18: warning: array subscript has type 'char' [-Wchar-subscripts]
        if(x!=x1[c])
                  ^
/in/foo.cc:29:18: warning: array subscript has type 'char' [-Wchar-subscripts]
            x=x1[c],y=y1[c];
                  ^
/in/foo.cc:29:26: warning: array subscript has type 'char' [-Wchar-subscripts]
            x=x1[c],y=y1[c];
                          ^
/in/foo.cc:29:26: warning: pointer to a function used in arithmetic [-Wpointer-arith]
/in/foo.cc:29:26: error: invalid conversion from 'double (*)(double) throw ()' to 'int' [-fpermissive]
            x=x1[c],y=y1[c];
                      ~~~~^
/in/foo.cc:31:18: warning: array subscript has type 'char' [-Wchar-subscripts]
            x=x2[c],y=y2[c];
                  ^
/in/foo.cc:31:26: warning: array subscript has type 'char' [-Wchar-subscripts]
            x=x2[c],y=y2[c];
                          ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:53:21: warning: array subscript has type 'char' [-Wchar-subscripts]
        if(x1[a[i][j]]==0)
                     ^
/in/foo.cc:54:22: warning: array subscript has type 'char' [-Wchar-subscripts]
            x1[a[i][j]]=i,y1[a[i][j]]=j;
                      ^
/in/foo.cc:54:36: warning: array subscript has type 'char' [-Wchar-subscripts]
            x1[a[i][j]]=i,y1[a[i][j]]=j;
                                    ^
/in/foo.cc:54:36: warning: pointer to a function used in arithmetic [-Wpointer-arith]
/in/foo.cc:54:38: error: assignment of read-only location '*(y1 + ((sizetype)a[i][j]))'
            x1[a[i][j]]=i,y1[a[i][j]]=j;
                                      ^
/in/foo.cc:54:38: error: cannot convert 'int' to 'double(double) throw ()' in assignment
/in/foo.cc:56:22: warning: array subscript has type 'char' [-Wchar-subscripts]
            x2[a[i][j]]=i,y2[a[i][j]]=j;
                      ^
/in/foo.cc:56:36: warning: array subscript has type 'char' [-Wchar-subscripts]
            x2[a[i][j]]=i,y2[a[i][j]]=j;
                                    ^