オフラインどう書く第12回 参考問題解答例(TypeScript)

class Turtle {
    private direction = 1;
    private pos = [0, 0];
    private way = 'A';
    private courseOut(course: string[]): boolean {
        return (
            course.length - 1 < this.pos[0] || this.pos[0] < 0 ||
            course[this.pos[0]][this.pos[1]] === '*' || course[this.pos[0]][this.pos[1]] === undefined);
    }
    turn(direction: string) {
        if (direction === 'L') {
            this.direction = this.direction === 0 ? 3 : this.direction - 1;
        } else {
            this.direction = this.direction === 3 ? 0 : this.direction + 1;
        }
    }
    walk(steps: number, directions: number[][], course: string[]) {
        for (var i = 0; i < steps; ++i) {
            this.pos[0] += directions[this.direction][0];
            this.pos[1] += directions[this.direction][1];
            if (this.pos[0] === course.length && this.direction === 2) {
                this.direction = 0;
                this.pos[0] -= 2;
                this.pos[1] = course[this.pos[0]].length - 1 - this.pos[1];
            }
            if (this.courseOut(course)) {
                this.way += '?';
                return;
            }
            this.way += course[this.pos[0]][this.pos[1]];
        }
    }
    getWay(): string {
        return this.way;
    }
}

var solve = (src: string): string => {
    var cource = [
        'ABCDEFGHIJK', 'LMNOPQRSTUV', 'WXYZabcdefg',
        'hij*****765', 'klm*****432', 'nop*****10z',
        'qrs*****yxw', 'tuv*****vut'];
    var directions = [[-1, 0], [0, 1], [1, 0], [0, -1]];
    var turtle = new Turtle();
    for (var i = 0; i < src.length; ++i) {
        var c = src[i];
        if (c === 'L' || c === 'R') {
            turtle.turn(c);
            continue;
        }
        var steps = parseInt(c, 16);
        turtle.walk(steps, directions, cource);
        if (turtle.getWay().indexOf('?') != -1) {
            break;
        }
    }
    return turtle.getWay();
}

var test = (src: string, expected: string) => {
    var actual = solve(src);
    var result = expected === actual ? 'ok' : '***ng***';
    console.log(result);
}