LeetCode8. 字符串转换整数 (atoi)

字符串转整数。链接：https://leetcode-cn.com/problems/string-to-integer-atoi/

题解：模拟题

class Solution {
public:
    int myAtoi(string str) {
        int flag = 0;
        long long temp = 0;
        for (int i = 0; i < str.length(); i++) {
            if (flag) {
                if (str[i] >= '0'&&str[i] <= '9') {
                    temp = temp * 10 + (str[i] - '0');
                    if (flag == -1) {
                        if (-temp < INT_MIN)return INT_MIN;
                    }
                    else if(flag==1){
                        if (temp > INT_MAX)return INT_MAX;
                    }
                }
                else {
                    if (flag == -1) return -temp;
                    return temp;
                }
            }
            else {
                if ( str[i]==' ')continue;
                else if(str[i]=='-'){
                    flag = -1;
                }
                else if (str[i] == '+') {
				flag = 1;
			    }
                else if (str[i]<'0' || str[i]>'9') {
                    return temp;
                }
                else {
                    flag = 1;
                    temp = str[i] - '0';
                }
            }
            //cout << "--------------" << temp << "-----------" << endl;
        }
        if (flag == -1) return -temp;
        return temp;
    }
};