Merge pull request xxg1413#24 from willalways/master

No.8,9

Author: willalways

8.String to Integer (atoi)/shadowcoder/StringtoInteger.c

@@ -0,0 +1,20 @@
+int myAtoi(char* str) {
+    int i = 0, flag = 1;
+    while(str[i] && str[i] == ' ') i += 1;
+    if (!str[i]) return 0;
+    if (str[i] == '-') {flag = -1;i+=1;}
+    else if(str[i] == '+') i+= 1;
+    
+    if (!isdigit(str[i])) return 0;
+    long long num = 0;
+    sscanf(str + i, "%lld", &num);
+    {
+        if (flag > 0) {
+            if (num > INT_MAX) return INT_MAX;
+            else return num;
+        } else {
+            if (-num < INT_MIN) return INT_MIN;
+            else return -num;
+        }
+    }
+}

9.Palindrome Number/shadowcoder/PalindromeNum.c

@@ -0,0 +1,11 @@
+bool isy(int x) {  
+    int y = 0;  
+    int origin = x;
+    if (x < 0) return 0;
+    while(x != 0) {  
+        y = y * 10 + x % 10;  
+        x /= 10;  
+    }  
+  
+    return y == origin ;  
+}