/*Constraint X[i] = (Y == i) */import cotfd;class Channel extends UserConstraint<CP>{	var<CP>{int}[] _x;	var<CP>{int} _y;		var<CP>{int}[] _vars;		int n;	Channel(var<CP>{int}[] x, var<CP>{int} y):UserConstraint<CP>(){		n = x.getSize();		_vars = new var<CP>{int}[1..n+1];		_x = new var<CP>{int}[1..n];		forall(i in 1..n){			_x[i] = x[i];			_vars[i] = x[i];		}		_y = y;		_vars[n+1] = y;	}		var<CP>{int}[] getIntVariables(){		return _vars;	}		Outcome<CP> post(Consistency<CP> cl){		//do a first propagation		Outcome<CP> resPropag = propagate();				forall( i in 1..n){			_x[i].addAC5Index(this,i);									}				_y.addAC5Index(this,1);				return resPropag;	}	//addAC5Index; 	Outcome<CP> valRemoveIdx(var<CP>{int}z, int idx, int val){		//when remove value val of _x[idx]		if(z.getId() == _x[idx].getId()){			if(val == 1){				if(_y.removeValue(idx) == Failure) return Failure;			}			else {								if(_y.bindValue(idx) == Failure) return Failure;			}		}		//when remove value val of _y		if(z.getId() == _y.getId()){			if(_x[val].removeValue(1) == Failure) return Failure;		}		return Suspend;	}	}Solver<CP> m();int t0 = System.getCPUTime();int n = 8; //1000;range S = 1..n;var<CP>{int} q[i in S](m,S);var<CP>{int}[] x[1..n];forall(i in S) x[i] = new var<CP>{int}[1..n](m,0..1);Integer np(m.getNPropag());cout << "Initiating search..." << endl;Integer c(0);solveall<m> {   forall(i in S)	   m.post(Channel(x[i],q[i]));   m.post(alldifferent(all(i in S) q[i] + i),onBounds);   m.post(alldifferent(all(i in S) q[i] - i),onBounds);   m.post(alldifferent(q),onBounds);     } using {    forall(i in S) label(x[i]);       c := c + 1;    cout << q << endl;}cout << "Nb : " << c << endl;int t1 = System.getCPUTime();cout << "time: " << t1 - t0 << endl;cout << "#choices = " << m.getNChoice() << endl;cout << "#fail    = " << m.getNFail() << endl;cout << "#propag  = " << m.getNPropag() - np << endl;