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@@ -0,0 +1,24 @@
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+class Solution {
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+ public int findKthNumber(int n, int k) {
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+ int cur = 1;
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+ k--;
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+ // Ten-ary tree
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+ while (0 < k) {
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+ int cnt = 0;
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+ long lo = cur, hi = cur + 1;
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+ while (lo <= n) {
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+ cnt += (int) (Math.min(hi, n + 1) - lo);
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+ lo *= 10;
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+ hi *= 10;
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+ } // Count the number of children level by level
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+ if (cnt <= k) {
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+ cur++; // Go to next child
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+ k -= cnt;
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+ } else {
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+ cur *= 10; // Go to next level
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+ k--;
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+ }
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+ }
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+ return cur;
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+ }
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+}
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