实现大整数相加

Posted 2021-01-23 dongma

static String bigNumberSum(String a,String b) {
        char[] charArrayA = new StringBuilder(a).reverse().toString().toCharArray();
        char[] charArrayB = new StringBuilder(b).reverse().toString().toCharArray();
        int length=charArrayA.length > charArrayB.length ? charArrayA.length : charArrayB.length;
        int[] result = new int[length +1];
        
        int temp=0;
        for(int i=0;i<result.length;i++) {
            temp=result[i];
            if(i < charArrayA.length) {
                temp+=charArrayA[i]-‘0‘;
            }
            if(i < charArrayB.length) {
                temp+=charArrayB[i]-‘0‘;
            }
            if(temp >= 10) {
                temp=temp-10;
                result[i+1]=1;
            }
            result[i]=temp;
        }
        StringBuilder sb=new StringBuilder();
        for(int i=0;i<result.length;i++) {
            if(i==length) {
                if(result[i]==0) {
                    break;
                }
            }
            sb.append(result[i]);
        }
        
        return sb.reverse().toString();
    }