// standard print functions
function print(s) {
    sys.print(s);
}
function println(s) {
    if (s === undefined)
        sys.print("\n");
    else
        sys.println(s);
}
function read() {
    return sys.read();
}
// ncurses-like terminal control
var con = {};
con.getch = function() {
    return sys.readKey();
};
con.move = function(y, x) {
    print(String.fromCharCode(27,91)+y+";"+x+"H");
};
con.addch = function(c) {
    graphics.putSymbol(c);
};
con.mvaddch = function(y, x, c) {
    move(y, x); addch(c);
};
con.getmaxyx = function() {
    return graphics.getTermDimension();
};
con.getyx = function() {
    return graphics.getCursorYX();
};
con.hitterminate = function() { // ^C
    sys.poke(-40, 1);
    return (sys.peek(-41) == 31 && (sys.peek(-42) == 129 || sys.peek(-42) == 130));
};
con.hiteof = function() { // ^D
    sys.poke(-40, 1);
    return (sys.peek(-41) == 32 && (sys.peek(-42) == 129 || sys.peek(-42) == 130));
};
con.resetkeybuf = function() {
    sys.poke(-40, 0);
    sys.poke(-41, 0); sys.poke(-42, 0); sys.poke(-43, 0); sys.poke(-44, 0);
    sys.poke(-45, 0); sys.poke(-46, 0); sys.poke(-47, 0); sys.poke(-48, 0);
};
con.color_fore = function(n) { // 0..7; -1 for transparent
    if (n < 0)
        print(String.fromCharCode(27,91)+"38;5;255m");
    else
        print(String.fromCharCode(27,91)+((n % 8)+30)+"m");
};
con.color_back = function(n) { // 0..7; -1 for transparent
    if (n < 0)
        print(String.fromCharCode(27,91)+"48;5;255m");
    else
        print(String.fromCharCode(27,91)+((n % 8)+40)+"m");
};
con.color_pair = function(fore, back) { // 0..255
    print(String.fromCharCode(27,91)+"38;5;"+fore+"m");
    print(String.fromCharCode(27,91)+"48;5;"+back+"m");
};
Object.freeze(con);
// system management  function
var system = {};
system.maxmem = function() {
    return sys.peek(-65) | (sys.peek(-66) << 8) | (sys.peek(-67) << 16) | (sys.peek(-68) << 24);
};
system.halt = function() {
    exit();
};
Object.freeze(system);
// some utilities functions
var base64 = {};
base64._lookup = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
base64._revLookup = {"":0,"=":0,"A":0,"B":1,"C":2,"D":3,"E":4,"F":5,"G":6,"H":7,"I":8,"J":9,"K":10,"L":11,"M":12,"N":13,"O":14,"P":15,"Q":16,"R":17,"S":18,"T":19,"U":20,"V":21,"W":22,"X":23,"Y":24,"Z":25,"a":26,"b":27,"c":28,"d":29,"e":30,"f":31,"g":32,"h":33,"i":34,"j":35,"k":36,"l":37,"m":38,"n":39,"o":40,"p":41,"q":42,"r":43,"s":44,"t":45,"u":46,"v":47,"w":48,"x":49,"y":50,"z":51,"0":52,"1":53,"2":54,"3":55,"4":56,"5":57,"6":58,"7":59,"8":60,"9":61,"+":62,"/":63};
base64.atobarr = function(base64str) {
    var modulo = base64str.length % 4;
    var ret = [];
    for (var i = 0; i < base64str.length + modulo; i += 4) {
        var bits = (base64._revLookup[base64str[i]] << 18) | (base64._revLookup[base64str[i+1]] << 12) | (base64._revLookup[base64str[i+2]] << 6) | (base64._revLookup[base64str[i+3]]);
        var pads = (base64str[i+2] == "=") ? 2 : ((base64str[i+3] == "=") ? 1 : 0);

        ret.push((bits >> 16) & 255);
        if (pads <= 1) ret.push((bits >> 8) & 255);
        if (pads == 0) ret.push(bits & 255);
    }
    return ret;
};
base64.atob = function(base64str) {
    var modulo = base64str.length % 4;
    var ret = "";
    for (var i = 0; i < base64str.length + modulo; i += 4) {
        var bits = (base64._revLookup[base64str[i]] << 18) | (base64._revLookup[base64str[i+1]] << 12) | (base64._revLookup[base64str[i+2]] << 6) | (base64._revLookup[base64str[i+3]]);
        var pads = (base64str[i+2] == "=") ? 2 : ((base64str[i+3] == "=") ? 1 : 0);

        ret += String.fromCharCode((bits >> 16) & 255);
        if (pads <= 1) ret += String.fromCharCode((bits >> 8) & 255);
        if (pads == 0) ret += String.fromCharCode(bits & 255);
    }
    return ret;
};
base64.btoa = function(inputString) {
    var modulo = inputString.length % 3;
    var outStr = "";
    if (Array.isArray(inputString)) {
        for (var i = 0; i < inputString.length + ((modulo == 0) ? 0 : 3 - modulo); i += 3) {
            var bytes = (inputString[i] << 16) | (inputString[i+1] << 8) | inputString[i+2];
            // for arrays, out-of-bounds have value of undefined;
            // for strings, out-of-bounds have value of NaN -- both are casted into int 0 on bitwise operations.

            outStr += base64._lookup[(bytes >> 18) & 63];
            outStr += base64._lookup[(bytes >> 12) & 63];
            if (i < Math.floor(inputString.length / 3) * 3 | (modulo == 2 || modulo == 0)) outStr += base64._lookup[(bytes >> 6) & 63];
            if (i < Math.floor(inputString.length / 3) * 3 | modulo == 0) outStr += base64._lookup[bytes & 63];
        }
        // pad the output
        if (modulo == 1) outStr += "==";
        else if (modulo == 2) outStr += "=";
    }
    else if (typeof inputString == "string") {
        for (var i = 0; i < inputString.length + ((modulo == 0) ? 0 : 3 - modulo); i += 3) {
            var bytes = (inputString.charCodeAt(i) << 16) | (inputString.charCodeAt(i+1) << 8) | inputString.charCodeAt(i+2);
            // for arrays, out-of-bounds have value of undefined;
            // for strings, out-of-bounds have value of NaN -- both are casted into int 0 on bitwise operations.

            outStr += base64._lookup[(bytes >> 18) & 63];
            outStr += base64._lookup[(bytes >> 12) & 63];
            if (i < Math.floor(inputString.length / 3) * 3 | (modulo == 2 || modulo == 0)) outStr += base64._lookup[(bytes >> 6) & 63];
            if (i < Math.floor(inputString.length / 3) * 3 | modulo == 0) outStr += base64._lookup[bytes & 63];
        }
        // pad the output
        if (modulo == 1) outStr += "==";
        else if (modulo == 2) outStr += "=";
    }
    else {
        throw "Unknown byte representation (with typeof "+typeof bytes+")";
    }

    return outStr;
};
Object.freeze(base64);
// Polyfilling some functions from ECMAScript6+
if (!String.prototype.repeat) {
    String.prototype.repeat = function(count) {
        'use strict';
        if (this == null)
            throw new TypeError('can\'t convert ' + this + ' to object');

        var str = '' + this;
        // To convert string to integer.
        count = +count;
        // Check NaN
        if (count != count)
            count = 0;

        if (count < 0)
            throw new RangeError('repeat count must be non-negative');

        if (count == Infinity)
            throw new RangeError('repeat count must be less than infinity');

        count = Math.floor(count);
        if (str.length == 0 || count == 0)
            return '';

        // Ensuring count is a 31-bit integer allows us to heavily optimize the
        // main part. But anyway, most current (August 2014) browsers can't handle
        // strings 1 << 28 chars or longer, so:
        if (str.length * count >= 1 << 28)
            throw new RangeError('repeat count must not overflow maximum string size');

        var maxCount = str.length * count;
        count = Math.floor(Math.log(count) / Math.log(2));
        while (count) {
             str += str;
             count--;
        }
        str += str.substring(0, maxCount - str.length);
        return str;
    }
}
if (!Array.prototype.filter){
    Array.prototype.filter = function(func, thisArg) {
        'use strict';
        if ( ! ((typeof func === 'Function' || typeof func === 'function') && this) )
                throw new TypeError();

        var len = this.length >>> 0,
                res = new Array(len), // preallocate array
                t = this, c = 0, i = -1;

        var kValue;
        if (thisArg === undefined){
            while (++i !== len){
                // checks to see if the key was set
                if (i in this){
                    kValue = t[i]; // in case t is changed in callback
                    if (func(t[i], i, t)){
                        res[c++] = kValue;
                    }
                }
            }
        }
        else{
            while (++i !== len){
                // checks to see if the key was set
                if (i in this){
                    kValue = t[i];
                    if (func.call(thisArg, t[i], i, t)){
                        res[c++] = kValue;
                    }
                }
            }
        }

        res.length = c; // shrink down array to proper size
        return res;
    };
}
// Production steps of ECMA-262, Edition 5, 15.4.4.19
// Reference: http://es5.github.io/#x15.4.4.19
if (!Array.prototype.map) {

    Array.prototype.map = function(callback/*, thisArg*/) {

        var T, A, k;

        if (this == null) {
            throw new TypeError('this is null or not defined');
        }

        // 1. Let O be the result of calling ToObject passing the |this|
        //    value as the argument.
        var O = Object(this);

        // 2. Let lenValue be the result of calling the Get internal
        //    method of O with the argument "length".
        // 3. Let len be ToUint32(lenValue).
        var len = O.length >>> 0;

        // 4. If IsCallable(callback) is false, throw a TypeError exception.
        // See: http://es5.github.com/#x9.11
        if (typeof callback !== 'function') {
            throw new TypeError(callback + ' is not a function');
        }

        // 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
        if (arguments.length > 1) {
            T = arguments[1];
        }

        // 6. Let A be a new array created as if by the expression new Array(len)
        //    where Array is the standard built-in constructor with that name and
        //    len is the value of len.
        A = new Array(len);

        // 7. Let k be 0
        k = 0;

        // 8. Repeat, while k < len
        while (k < len) {

            var kValue, mappedValue;

            // a. Let Pk be ToString(k).
            //   This is implicit for LHS operands of the in operator
            // b. Let kPresent be the result of calling the HasProperty internal
            //    method of O with argument Pk.
            //   This step can be combined with c
            // c. If kPresent is true, then
            if (k in O) {

                // i. Let kValue be the result of calling the Get internal
                //    method of O with argument Pk.
                kValue = O[k];

                // ii. Let mappedValue be the result of calling the Call internal
                //     method of callback with T as the this value and argument
                //     list containing kValue, k, and O.
                mappedValue = callback.call(T, kValue, k, O);

                // iii. Call the DefineOwnProperty internal method of A with arguments
                // Pk, Property Descriptor
                // { Value: mappedValue,
                //   Writable: true,
                //   Enumerable: true,
                //   Configurable: true },
                // and false.

                // In browsers that support Object.defineProperty, use the following:
                // Object.defineProperty(A, k, {
                //   value: mappedValue,
                //   writable: true,
                //   enumerable: true,
                //   configurable: true
                // });

                // For best browser support, use the following:
                A[k] = mappedValue;
            }
            // d. Increase k by 1.
            k++;
        }

        // 9. return A
        return A;
    };
}
// Production steps of ECMA-262, Edition 5, 15.4.4.21
// Reference: http://es5.github.io/#x15.4.4.21
// https://tc39.github.io/ecma262/#sec-array.prototype.reduce
if (!Array.prototype.reduce) {
    Object.defineProperty(Array.prototype, 'reduce', {
        value: function(callback /*, initialValue*/) {
            if (this === null) {
                throw new TypeError( 'Array.prototype.reduce ' +
                    'called on null or undefined' );
            }
            if (typeof callback !== 'function') {
                throw new TypeError( callback +
                    ' is not a function');
            }

            // 1. Let O be ? ToObject(this value).
            var o = Object(this);

            // 2. Let len be ? ToLength(? Get(O, "length")).
            var len = o.length >>> 0;

            // Steps 3, 4, 5, 6, 7
            var k = 0;
            var value;

            if (arguments.length >= 2) {
                value = arguments[1];
            } else {
                while (k < len && !(k in o)) {
                    k++;
                }

                // 3. If len is 0 and initialValue is not present,
                //    throw a TypeError exception.
                if (k >= len) {
                    throw new TypeError( 'Reduce of empty array ' +
                        'with no initial value' );
                }
                value = o[k++];
            }

            // 8. Repeat, while k < len
            while (k < len) {
                // a. Let Pk be ! ToString(k).
                // b. Let kPresent be ? HasProperty(O, Pk).
                // c. If kPresent is true, then
                //    i.  Let kValue be ? Get(O, Pk).
                //    ii. Let accumulator be ? Call(
                //          callbackfn, undefined,
                //          « accumulator, kValue, k, O »).
                if (k in o) {
                    value = callback(value, o[k], k, o);
                }

                // d. Increase k by 1.
                k++;
            }

            // 9. Return accumulator.
            return value;
        }
    });
}
// Production steps of ECMA-262, Edition 5, 15.4.4.22
// Reference: http://es5.github.io/#x15.4.4.22
if ('function' !== typeof Array.prototype.reduceRight) {
    Array.prototype.reduceRight = function(callback /*, initialValue*/) {
        'use strict';
        if (null === this || 'undefined' === typeof this) {
            throw new TypeError('Array.prototype.reduce called on null or undefined');
        }
        if ('function' !== typeof callback) {
            throw new TypeError(callback + ' is not a function');
        }
        var t = Object(this), len = t.length >>> 0, k = len - 1, value;
        if (arguments.length >= 2) {
            value = arguments[1];
        } else {
            while (k >= 0 && !(k in t)) {
                k--;
            }
            if (k < 0) {
                throw new TypeError('Reduce of empty array with no initial value');
            }
            value = t[k--];
        }
        for (; k >= 0; k--) {
            if (k in t) {
                value = callback(value, t[k], k, t);
            }
        }
        return value;
    };
}