PHP练习-计算两个超大整数相加的结果
2020-09-04 16:44 By
"Powerless"
2811
2
1
思路分析
将超大整数逐个拆分位单个字符，按位相加。
function sumStr($str1,$str2)
{
$c1 = strlen($str1)-1;
$c2 = strlen($str2)-1;
$i = $c1 > $c2 ? $c1 : $c2;
$str = '';
$surplus = 0;
for (; $i>=0; $i--,$c1--,$c2--){
$sum = 0;
if($c1 >= 0 && $c2 >= 0){
$sum = $str1[$c1] + $str2[$c2] + $surplus;
}elseif($c1 < 0){
$sum = $str2[$c2] + $surplus;
}elseif($c2 < 0){
$sum = $str1[$c1] + $surplus;
}
if($sum > 9){
$str[$i] = $sum - 10;
$surplus = 1;
}else{
$str[$i] = $sum;
$surplus = 0;
}
if(!$i && $surplus){
$str = $surplus.$str;
}
}
return $str;
}
$s1 = '897685675463468768967';
$s2 = '42423476898765356';
echo sumStr($s1,$s2);
输出结果：897728098940367534323
View in WeChat
Others Discussion
-
2016年云计算热词 Posted on 2019-06-12 17:53
-
PHP没你想的那么差 Posted on 2021-12-17 15:40
-
Mysql联合索引的最左前缀匹配原则 Posted on 2018-08-25 15:00
-
巧用CAS解决数据一致性问题 Posted on 2019-03-07 11:55
-
分布式架构之「 数据分布」 Posted on 2019-11-14 10:00
-
PHP扩展ImageMagick安装 Posted on 2022-11-11 11:16
-
通过信鸽来解释HTTPS Posted on 2018-10-22 13:56
-
HTTP和HTTPS的区别 Posted on 2020-08-10 23:00
评 论