请帮我把下面的数字换算成2进制

15 =1* 2^3 + 1*2^2 + 1*2^1 + 1*2^0
= (1111)

45 = 1* 2^5 + 1*2^3 + 1*2^2 + 1*2^0
=(101101)

18 = 1*2^4 + 1*2^1
=(10010)

61 = 1*2^5 + 1*2^4 + 1*2^3 + 1*2^2 + 1^2^0
=(111101)

如果数目较大，给你个转换方法：

十进制转二进制：
用2辗转相除至结果为1
将余数和最后的1从下向上倒序写 就是结果
例如302
302/2 = 151 余0
151/2 = 75 余1
75/2 = 37 余1
37/2 = 18 余1
18/2 = 9 余0
9/2 = 4 余1
4/2 = 2 余0
2/2 = 1 余0
故二进制为100101110

15451861

15451861/2=7725930....1
7725930/2=3862965.....0
3862965/2=1931482.....1
1931482/2=965741......0
965741/2=482870.......1
482870/2=241435.......0
241435/2=120717.......1
120717/2=60358........1
60358/2=30179.........0
30179/2=15089.........1
15089/2=7544..........1
7544/2=3772...........0
3772/2=1886...........0
1886/2=943............0
943/2=471.............1
471/2=23