大数相加

￡神魔★判官ぃ 2022-08-11 10:59 3阅读 0赞

<pre name="code" class="java">package com.zhiru;
    
    /*
     * 大数加法。
     */
    public class BigDataAdd {
    
    	public static boolean isDigit(String s) {
    		int i = 0;
    		boolean res = false;
    		while (i < s.length()) {
    			char x = s.charAt(i);
    			if (x >= '0' && x <= '9') {
    				i++;
    				res = true;
    			} else {
    				res = false;
    				break;
    			}
    		}
    		return res;
    	}
    
    	public static void bigDataAdd(String a, String b) {
    		int l1 = a.length();
    		int l2 = b.length();
    		if ((a != null && l1 > 0) && (b != null && l2 > 0)) {
    			int maxLen = l1 > l2 ? l1 : l2;
    			int k = maxLen;
    			if (isDigit(a) && isDigit(b)) {
    				int[] a1 = new int[maxLen + 1];
    				int[] a2 = new int[maxLen + 1];
    				for (int i = k, j = l1 - 1; j >= 0; i--, j--) {
    					a1[i] = a.charAt(j) - '0';
    				}
    				for (int m = k, n = l2 - 1; n >= 0; m--, n--) {
    					a2[m] = b.charAt(n) - '0';
    				}
    				for (int p = k; p > 0; p--) {
    					a1[p] += a2[p];
    					if (a1[p] >= 10) {
    						a1[p] -= 10;
    						a1[p - 1]++;
    					}
    				}
    				if (a1[0] != 0) {
    					System.out.print(a + " " + b + "和为" + (k + 1) + "位长\n");
    					for (int i = 0; i <= k; i++) {
    						System.out.print(a1[i]);
    					}
    				} else {
    					System.out.print(a + " " + b + "和为" + (k) + "位长\n");
    					for (int i = 1; i <= k; i++) {
    						System.out.print(a1[i]);
    					}
    				}
    
    			}
    			else{
    				System.out.print("参数中含有非法字符!\n");
    			}
    		} else {
    			System.out.print("参数为null\n");
    		}
    	}
    
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    
    		bigDataAdd("", "");
    		bigDataAdd(" "," ");
    		bigDataAdd("-1214 fe AGE","123 456 789 ");
    		bigDataAdd("1234567890", "0987654321");
    	}
    
    }

参数为null  
参数中含有非法字符!  
参数中含有非法字符!  
1234567890 0987654321和为10位长  
2222222211