%
% Ramsey
%

int: N = 10;

array[1..N,1..N] of var 0..1 : R;
array[1..N,1..N] of var 0..1 : G;
array[1..N,1..N] of var 0..1 : B;

% on colorie un arc en Rouge, Vert ou Bleu
constraint forall(i in 1..N-1) (
  forall(j in i+1..N) (
      R[i,j] + G[i,j] + B[i,j] = 1
    )
);