PROBLEM DESCRIPTION
Given a number N. Find the length of the longest consecutive 1s in its binary representation.
SOLUTION
APPROACH 1
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class Solution{
public static int maxConsecutiveOnes(int n) {
int max = 0;
int current = 0;
while(n != 0){
if((n&1) != 0){
current++;
}else{
current = 0;
}
max = Math.max(max, current);
n = n >> 1;
}
return max;
}
}
APPROACH 2
By taking the bitwise AND (&) of N and N left-shifted by 1, we effectively “erase” the trailing 1 from every sequence of consecutive 1s. This reduces the number of consecutive 1s in each iteration, helping us count their length.
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class Solution{
public static int maxConsecutiveOnes(int n) {
int count = 0;
while(n != 0){
n = (n & (n << 1)); // right shift would also work with the same logic
count++;
}
return count;
}
}