hammingDistance method
比较两个长度一样的字符串有几个字符不同
Implementation
int hammingDistance(String str1, String str2) {
if (str1.length != str2.length) {
throw FormatException('Strings must have the same length');
}
var l1 = str1.runes.toList();
var l2 = str2.runes.toList();
var distance = 0;
for (var i = 0; i < l1.length; i++) {
if (l1[i] != l2[i]) {
distance++;
}
}
return distance;
}