g0301_0400.s0338_counting_bits.Solution Maven / Gradle / Ivy
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Java-based LeetCode algorithm problem solutions, regularly updated
package g0301_0400.s0338_counting_bits;
// #Easy #Dynamic_Programming #Bit_Manipulation #Udemy_Bit_Manipulation
// #Big_O_Time_O(num)_Space_O(num) #2022_07_10_Time_2_ms_(86.73%)_Space_48.3_MB_(31.59%)
public class Solution {
public int[] countBits(int num) {
int[] result = new int[num + 1];
int borderPos = 1;
int incrPos = 1;
for (int i = 1; i < result.length; i++) {
// when we reach pow of 2 , reset borderPos and incrPos
if (incrPos == borderPos) {
result[i] = 1;
incrPos = 1;
borderPos = i;
} else {
result[i] = 1 + result[incrPos++];
}
}
return result;
}
}