% rope_intranet.pi (in Picat)
% authors:  Mike Bionchik, Neng-Fa Zhou
% date:  06/16/2015
% https://code.google.com/codejam/contest/619102/dashboard#s=p0
% Round 1C 2010
% Problem A. Rope Intranet
%
% to use: picat rope_intranet < input_file > output_file
%

main =>
    T = read_int(stdin),
    foreach(TC in 1..T)
        N = read_int(stdin),
    	Wires = {(read_int(stdin),read_int(stdin)) : _ in 1..N},
        do_case(TC,Wires)
    end.

do_case(TC,Wires) =>
    Count = sum([intersect(Wires[I],Wires[J]) : I in 1..len(Wires), J in I+1..len(Wires)]),
    writef("Case #%w: %w%n", TC, Count).

intersect((L1,R1),(L2,R2)) = Res, (L1>L2 && R1<R2 || L1<L2 && R1>R2) => Res = 1.
intersect(_,_) = 0.

picat-lang.org