之前我们做过这道题,今天还是一堆问题,不慌,不乱,要镇定,真正理解,过遍数。
public boolean isPalindrome(String s) {
if (s == null || s.length() < 2) {
return true;
}
s = s.toLowerCase();
char h1 = 'a', l1 = 'z';
char h2 = '0', l2 = '9';
int left = 0, right = s.length() - 1;
while (left < right) {
if (!((s.charAt(left) >= h1 && s.charAt(left) <= l1) || (s.charAt(left) >= h2 && s.charAt(left) <= l2))) {
left++;
continue;
}
if (!((s.charAt(right) >= h1 && s.charAt(right) <= l1) || (s.charAt(right) >= h2 && s.charAt(right) <= l2))) {
right--;
continue;
}
if (s.charAt(left) == s.charAt(right)) {
left++;
right--;
} else {
return false;
}
}
return true;
}
// public boolean isPalindrome(String s) {
// if (s == null || s.length() < 2) {
// return true;
// }
// int length = s.length();
// boolean odd = (length % 2) == 1 ? true : false;
// int left = 0, right = length - 1;
// while (left < right) {
// if (!((s.charAt(left) >= 'A' && s.charAt(left) <= 'Z') || (s.charAt(left) >= 'a' && s.charAt(left) <= 'z'))) {
// left++;
// continue;
// }
// if (!((s.charAt(right) >= 'A' && s.charAt(right) <= 'Z') || (s.charAt(right) >= 'a' && s.charAt(right) <= 'z'))) {
// right--;
// continue;
// }
// //if ((s.charAt(left) != s.charAt(right)) || (Math.abs(s.charAt(left) - s.charAt(right)) != 32)) {
// if ((s.charAt(left) != s.charAt(right))) {
// if ((Math.abs(s.charAt(left) - s.charAt(right)) == 32)) {
// left++;
// right--;
// continue;
// }
// return false;
// }
// left++;
// right--;
// }
// return true;
// }