{"trustable":false,"sections":[{"title":"","value":{"format":"MD","content":"求出区间[a,b]中有多少个数能够写成 K 个 B 的不同幂次之和。\n\n数据范围:1≤a≤b≤2^31-1, 1≤k≤20, 2≤B≤10。\n\n17 \u003d 2^4 + 2^0\n18 \u003d 2^4 + 2^1\n20 \u003d 2^4 + 2^2"}},{"title":"Input","value":{"format":"MD","content":"单组输入\n第一行两个整数a, b \n接下来两行分别为K,B\n "}},{"title":"Output","value":{"format":"MD","content":"输出一个整数,即个数。"}},{"title":"Sample Iutput","value":{"format":"MD","content":"15 20\n2\n2\n\n\n "}},{"title":"Sample Output","value":{"format":"MD","content":"3\n"}}]}