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package state.four;
interface I {
public int f();
public int g();
public void changeDirection();
}
class C implements I {
private CState state = new CStateMinus(this);
int i;
int j;
public int f() {
return state.f();
}
public int g() {
return state.g();
}
public void changeDirection() {
state = state.next();
}
}
interface CState {
public int f();
public int g();
public CState next();
}
class CStateMinus implements CState {
C x;
CStateMinus(C x) { this.x = x; }
public int f() {
x.i -= 32;
return x.i;
}
public int g() {
x.j -= 27;
return x.j;
}
public CState next() {
return new CStatePlus(x);
}
}
class CStatePlus implements CState {
C x;
CStatePlus(C x) { this.x = x; }
public int f() {
x.i += 26;
return x.i;
}
public int g() {
x.j += 42;
return x.j;
}
public CState next() {
return new CStateMinus(x);
}
}
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