http://www.codingame.com/puzzles Skynet: the Chasm

solve.js

var R = parseInt(readline()) - 1; // the length of the road before the gap.
var G = parseInt(readline()); // the length of the gap.
var L = parseInt(readline()); // the length of the landing platform.
var S, X;
var t = 0;
var remaining, S_needed, t_accel, t_adjust;
var initialized;

function dist(S_initial, S_needed) {
    var d = 0, s;
    if (S_initial < S_needed) {
        for (s = S_initial; s < S_needed; s++) {
            d += s + 1;
        }
    } else {
        for (s = S_initial; S_needed < s; s--) {
            d += s - 1;
        }
    }
    return d;
}

while (true) {
    S = parseInt(readline()); // the motorbike's speed.
    X = parseInt(readline()); // the position on the road of the motorbike.
    
    if (!initialized) {
        S_needed = G + 1;
        t_accel = Math.abs(S_needed - S);
        remaining = R - dist(S, S_needed);
        t_adjust = remaining % S_needed;
        initialized = true;
    }
    
    if (t < t_adjust) {
        print('WAIT');
    } else if (t < t_accel + t_adjust) {
        if (S < S_needed) {
            print('SPEED');
        } else if (S_needed < S) {
            print('SLOW');
        }
    } else if (X < R) {
        print('WAIT');
    } else if (X === R) {
        print('JUMP');
    } else {
        print('SLOW');
    }
    
    t++;
}