[LeetCode]8. String to Integer (atoi)
原题链接:https://leetcode.com/problems/string-to-integer-atoi/description/
意思是把输入的字符串string转为int。然后会有错误输入,要对这些进行处理。具体要求为Requirements for atoi:
我的实现:
class Solution { public: int myAtoi(string str) { bool initialSign = true; bool isPositive = true; int result = 0; for (int i = 0; i < str.length(); i++) { if (str[i] == '+' && initialSign) { isPositive = true; initialSign = false; } else if (str[i] == '-' && initialSign) { isPositive = false; initialSign = false; } else if (str[i] >= '0' && str[i] <= '9') { if ((abs(result) > (INT_MAX / 10) && isPositive) || (abs(result) == (INT_MAX / 10) && str[i] > '7' && isPositive)) return INT_MAX; else if ((abs(result) > (INT_MAX / 10) && !isPositive) || (abs(result) == (INT_MAX / 10) && str[i] > '8' && !isPositive)) return INT_MIN; result = result * 10 + (str[i] - '0'); initialSign = false; } else if (!initialSign || str[i] != ' ') { return isPositive ? result : -1*result; } } return isPositive ? result : -1*result; } };
总结:仔细考虑错误输入,溢出处理同[LeetCode]7. Reverse Integer。