Create 9.cpp

LeetCode-CN/9.cpp

@@ -0,0 +1,37 @@
+#include <cstdio>
+class Solution {
+public:
+    bool isPalindrome(int x) {
+        /*
+        // Converting to string is too slow!!
+        char buff[64] = { 0 };
+        sprintf(buff, "%d", x);
+        int len = strlen(buff);
+        int L = 0, R = len - 1;
+        while (L < R)
+        {
+            if (buff[L] != buff[R]) return false;
+            ++L;
+            --R;
+        }
+        return true;
+        */
+        if (x < 0) return false;
+        int buff[64] = { 0 };
+        int c = 0;
+        int tx = x;
+        while (tx > 0)
+        {
+            buff[c++] = tx % 10;
+            tx /= 10;
+        }
+        int L = 0, R = c - 1;
+        while (L < R)
+        {
+            if (buff[L] != buff[R]) return false;
+            ++L;
+            --R;
+        }
+        return true;
+    }
+};