Given an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n.
For example:
Given n = 13,
Return 6, because digit 1 occurred in the following numbers: 1, 10, 11, 12, 13.
Hint:
public int countDigitOne(int n) {
int ones = 0;
for (long m = 1; m <= n; m *= 10) {
long a = n / m, b = n % m;
ones += (a + 8) / 10 * m;
if (a % 10 == 1)
ones += b + 1;
}
return ones;
}
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。
原创声明:本文系作者授权腾讯云开发者社区发表,未经许可,不得转载。
如有侵权,请联系 cloudcommunity@tencent.com 删除。