Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.
Example 1:
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Input: 121
Output: true
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Example 2:
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Input: -121
Output: false
Explanation: From left to right, it reads -121. From right to left, it becomes 121-. Therefore it is not a palindrome.
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Example 3:
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Input: 10
Output: false
Explanation: Reads 01 from right to left. Therefore it is not a palindrome.
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Follow up:
Coud you solve it without converting the integer to a string?
算法思想和第7题差不多，而且说了不让用string，就是第7题之后加个判断，感觉自己在偷懒，但是还是想了好长时间才想出来。
Solution：
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class {
public:
bool isPalindrome(int x) {
int res = 0, tmp = x;
if (x < 0)
return false;
while (tmp != 0) {
int pop = tmp % 10;
tmp /= 10;
if (res > INT_MAX/10 || (res == INT_MAX / 10 && pop > 7)) return 0;
if (res < INT_MIN/10 || (res == INT_MIN / 10 && pop < -8)) return 0;
res = res * 10 + pop;
}
if (res == x)
return true;
else
return false;
}
};
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| Time Submitted |
Status |
Runtime |
Memory |
Language |
| a few seconds ago |
Accepted |
32 ms |
8 MB |
cpp |
最近负能量有点多，需要心灵鸡汤透一透，最好是喝完能上头的那种。
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