diff options
-rw-r--r-- | total_hamming_distance.c | 25 | ||||
-rw-r--r-- | total_hamming_distance.py | 27 |
2 files changed, 52 insertions, 0 deletions
diff --git a/total_hamming_distance.c b/total_hamming_distance.c new file mode 100644 index 0000000..571f417 --- /dev/null +++ b/total_hamming_distance.c @@ -0,0 +1,25 @@ +// 477. Total Hamming Distance +#include "leetcode.h" + +/* + * the hamming distance between two integers is the number of positions at which + * the corresponding bits are different. given an integer array 'nums', return + * the sum of hamming distances between all the pairs of the integers in 'nums'. + */ + +int totalHammingDistance(int *nums, int numsSize) { + int total = 0; + for (int i = 0; i < 32; i++) { + int cnt = 0; + for (int j = 0; j < numsSize; j++) + cnt += (nums[j] >> i) & 1; + total += cnt * (numsSize - cnt); + } + return total; +} + +int main() { + int n1[] = {4, 14, 2}, n2[] = {4, 14, 4}; + printf("%d\n", totalHammingDistance(n1, ARRAY_SIZE(n1))); // expect: 6 + printf("%d\n", totalHammingDistance(n2, ARRAY_SIZE(n2))); // expect: 4 +} diff --git a/total_hamming_distance.py b/total_hamming_distance.py new file mode 100644 index 0000000..3098372 --- /dev/null +++ b/total_hamming_distance.py @@ -0,0 +1,27 @@ +# 477. Total Hamming Distance + +""" +the hamming distance between two integers is the number of positions at which +the corresponding bits are different. given an integer array 'nums', return +the sum of hamming distances between all the pairs of the integers in 'nums'. +""" + + +class Solution(object): + def totalHammingDistance(self, nums): + """ + :type nums: List[int] + :rtype: int + """ + bits = [[0, 0] for _ in range(32)] + for i in nums: + for j in bits: + j[i % 2] += 1 + i /= 2 + return sum(x * y for x, y in bits) + + +if __name__ == "__main__": + obj = Solution() + print(obj.totalHammingDistance(nums=[4, 14, 2])) + print(obj.totalHammingDistance(nums=[4, 14, 4])) |