% bot_trust.pi (in Picat)
% by B.Y. Zhou, Jan. 2, 2016
% https://code.google.com/codejam/contest/975485/dashboard#s=p0
% Qualification Round 2011
% Problem A. Bot Trust
%
% to use: picat bot_trust < input_file > output_file
%
main =>
    T = read_int(),
    foreach (TC in 1..T)
        do_case(TC)
    end.

do_case(TC) =>
    Op = 1, % Last orange robot position
    Ot = 0, % Last orange robot update
    Bp = 1, % Last blue robot position
    Bt = 0, % Last blue robot update
    Tt = 0, % Total time elapsed
    N = read_int(),

    foreach(I in 1..N)
        Trn = read_char(),
        Pos = read_int(),
        if Trn == 'O' then % Orange turn
            Tt := Tt + 1 + max(abs(Op - Pos) - (Tt - Ot), 0),
            Ot := Tt,
            Op := Pos
        else % Blue turn
            Tt := Tt + 1 + max(abs(Bp - Pos) - (Tt - Bt), 0),
            Bt := Tt,
            Bp := Pos
        end
    end,
    printf("Case #%w: %w\n",TC, Tt).

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