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Add Binary

Given two binary strings, return their sum (also a binary string).

For example,
a = "11"
b = "1"

Return "100".

public class Solution {
    public String addBinary(String a, String b) {
        int alen=a.length();
    	int blen=b.length();
    	int len=alen>blen?

(alen+1):(blen+1); StringBuffer sba=new StringBuffer(a).reverse(); StringBuffer sbb=new StringBuffer(b).reverse(); while(sba.length()<len) sba.append("0"); while(sbb.length()<len) sbb.append("0"); StringBuffer sb=new StringBuffer(""); int tmp = 0; for(int i=0;i<len;i++){ int ia=(int) (sba.charAt(i)-‘0‘); int ib=(int) (sbb.charAt(i)-‘0‘); int ic=ia+ib+tmp; tmp=0; if(ic==3){ sb.append("1"); tmp=1; } else if( ic==2){ sb.append("0"); tmp=1; } else{ new String(); sb.append(String.valueOf(ic)); tmp=0; } } // if last is 0 ; then delete if(sb.charAt(sb.length()-1)==‘0‘) sb.deleteCharAt(sb.length()-1); return sb.reverse().toString(); } }


Add Binary