字符串转换完成

三数之和待优化
2024-12-28 18:47:03 +08:00
commit 759c5b09ce
3 changed files with 111 additions and 0 deletions
--- a/myAtoi.cpp
+++ b/myAtoi.cpp
@@ -0,0 +1,57 @@
+#include <iostream>
+#include <math.h>
+#include <memory>
+#include <string>
+
+using namespace std;
+
+string test = "-91283472332";
+
+class Solution
+{
+public:
+    int myAtoi(string s)
+    {
+        auto i = s.begin();
+        long long toReturn = 0;
+        while (*i == ' ') {
+            i++;
+        }
+        auto head = i;
+        i++;
+        while ((('0' <= *i) and (*i <= '9'))) {
+            i++;
+        }
+        auto end = i++;
+        i = head;
+        if ((('0' <= *i) and (*i <= '9')) or (*i == '-')) {
+            while ('0' <= *i <= '9') {
+                i++;
+                if (i == end) {
+                    break;
+                }
+            }
+            i--;
+            long long carry = 0;
+            while (i != head) {
+                toReturn += pow(10, carry) * ((*i) - 48);
+                i--;
+                carry++;
+            }
+            if (*i == '-') {
+                return -toReturn;
+            } else {
+                return toReturn + pow(10, carry) * ((*i) - 48);
+            }
+        } else {
+            return 0;
+        }
+    }
+};
+
+int main()
+{
+    Solution s;
+    cout << s.myAtoi(test) << endl;
+    return 0;
+}