View Compilation Error

0_0_18577390_29283.cpp: In function 'int main()':
0_0_18577390_29283.cpp:5:14: error: redeclaration of 'int X2'
 int X1,Y1,X2,X2,D1,D2;
              ^
0_0_18577390_29283.cpp:5:11: note: 'int X2' previously declared here
 int X1,Y1,X2,X2,D1,D2;
           ^
0_0_18577390_29283.cpp:7:26: error: '$X2' was not declared in this scope
 scanf("%d%d%d%d",&X1,&Y1,$X2,&Y2);
                          ^
0_0_18577390_29283.cpp:7:31: error: 'Y2' was not declared in this scope
 scanf("%d%d%d%d",&X1,&Y1,$X2,&Y2);
                               ^