java是一种可以撰写跨平台应用软件的面向对象的程序设计语言，是由Sun Microsystems公司于1995年5月推出的Java程序设计语言和Java平台（即JavaEE, JavaME, JavaSE）的总称。本站提供基于Java框架struts,spring,hibernate等的桌面应用、web交互及移动终端的开发技巧与资料

保持永久学习的心态，将成就一个优秀的你，来 继续搞起java知识。

Implement atoi to convert a string to an integer.

Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases.

Notes: It is intended for this problem to be specified vaguely (ie, no given input specs). You are responsible to gather all the input requirements up front.

public class Solution {

	public int myAtoi(String str) {
		if(str.equals("")){
			return 0;
		}
        char[] chs = str.toCharArray();
        int len = chs.length;
        double sum = 0;
        /*for(int i = 0;i<len;i++){
        	if(chs[i]==&#39; &#39;){
        		chs[i]=&#39;0&#39;;
        	}
        }*/
        int j = 0;
        int a = -1;
        while(chs[j]==&#39; &#39;){
        	a = j;
        	j++;
        }
        int b = a+1;
        //System.out.println(b);
        for(int r = b+1;r<len;r++){
        	if(chs[r]<&#39;0&#39; || chs[r]>&#39;9&#39;){
        		len = r;
        		break;
        	}
        }
        //System.out.println(len);
        if(chs[b]==&#39;+&#39;){
        	for(int i = b+1;i<len;i++){
        		if(chs[i]>=&#39;0&#39; && chs[i]<=&#39;9&#39;){
        			sum+=(chs[i]-&#39;0&#39;)*Math.pow(10, len-i-1);
        		}if(chs[i]==&#39; &#39;){
        			return (int) ((int) sum/Math.pow(10, len-i));
        		}else 
        			
        			if(chs[i]<&#39;0&#39; || chs[i]>&#39;9&#39;){
        			return (int) ((int) sum/Math.pow(10, len-i));
        		}
            }
        }else if(chs[b]==&#39;-&#39;){
        	for(int i = b+1;i<len;i++){
        		if(chs[i]>=&#39;0&#39; && chs[i]<=&#39;9&#39;){
        			sum+=(chs[i]-&#39;0&#39;)*Math.pow(10, len-i-1);
        		}if(chs[i]==&#39; &#39;){
        			return (int) ((int) sum/Math.pow(10, len-i));
        		}else if(chs[i]<&#39;0&#39; || chs[i]>&#39;9&#39;){
        			return (int) ((int) (-1)*((int) sum/Math.pow(10, len-i)));
        		}
            }
        	sum = (-1)*sum;
        }else{
        	for(int i = b;i<len;i++){
        		if(chs[i]>=&#39;0&#39; && chs[i]<=&#39;9&#39;){
        			sum+=(chs[i]-&#39;0&#39;)*Math.pow(10, len-i-1);
        		}if(chs[i]==&#39; &#39;){
        			return (int) ((int) sum/Math.pow(10, len-i));
        		}else if(chs[i]<&#39;0&#39; || chs[i]>&#39;9&#39;){
        			return (int) ((int) sum/Math.pow(10, len-i));
        		}
            }
        }
        if(sum>Integer.MAX_VALUE ){
        	return Integer.MAX_VALUE;
        }
        if(sum<Integer.MIN_VALUE){
        	return Integer.MIN_VALUE;
        }
        return (int)sum;
    }
	public static void main(String[] args) {
		System.out.println(new Solution().myAtoi("   -1123u3761867"));

	}

}

javaleetcode代码

因为水平有限，难免有疏忽或者不准确的地方，希望大家能够直接指出来，我会及时改正。一切为了知识的分享。

后续会有更多的精彩的内容分享给大家。