Palindrome number

Signed-off-by: begeekmyfriend <[email protected]>

009_palindrome_number/Makefile

@@ -0,0 +1,2 @@
+all:
+	gcc -O2 -o test palindrome_number.c

009_palindrome_number/palindrome_number.c

@@ -0,0 +1,34 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+static int reverse(int x)
+{
+    int y = 0;
+    while (x) {
+        y = y * 10 + x % 10;
+        x /= 10;
+    }
+    return y;
+}
+
+static bool isPalindrome(int x) {
+    if (x == 0) {
+        return true;
+    }
+    if (x < 0) {
+        return false;
+    }
+    return x == reverse(x);
+}
+
+int main(int argc, char **argv)
+{
+    if (argc < 2) {
+        fprintf(stderr, "Usage: ./test number\n");
+        exit(-1);
+    }
+
+    printf("%s\n", isPalindrome(atoi(argv[1])) ? "true" : "false");
+    return 0;
+}