import math
def getIntputs():
    angle = eval(input('please input angle'))
    vel = eval(input('please input vel'))
    h0 = eval(input('please input h0'))
    time = eval(input('please input time'))
    return angle, vel, h0, time
#shot类的定义
class Shot:
    def __init__(self, angle, vel, h0):
        theta = math.radians(angle)
        self.xvel = vel*math.cos(theta)
        self.yvel = vel*math.sin(theta)
        self.xpos = 0
        self.ypos = h0
    def getX(self):
        return self.xpos

    def getY(self):
        return self.ypos

    def update(self, time):
        Yyvel = self.yvel - 9.8*time
        self.xpos = self.xpos + Yyvel*time
        self.ypos = self.ypos - Yyvel*time/2
        self.yvel = Yyvel

#输出函数
def main():
    angle, vel, h0, time = getIntputs()
    shot = Shot(angle, vel, h0)
    while shot.getY() >= 0:
        shot.update(time)
    print('水平距离为:{0:0.1f}meter'.format(shot.getX()))

if __name__ == '__main__':
    main()