[Codewars] 4 kyu - Sum Strings as Numbers

題意

大數相加。

程式

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function sumStrings(a,b) {
if ( b.length > a.length ){
var temp = a ;
a = b ;
b = temp ;
}
while ( b.length < a.length ){
b = '0' + b ;
}
a = a.split('').reverse().join('');
b = b.split('').reverse().join('');
var c = '' , i = 0 ;
var carry = 0 ;
for ( var i = 0 ; i < a.length ; i ++ ) {
var result = parseInt(a[i]) + parseInt(b[i]) + carry ;
carry = 0 ;
if ( result >= 10 ){
result -= 10 ;
carry ++ ;
}
c = c + result;
}
if ( carry !== 0 ){
c = c + '1' ;
}
while ( c[c.length-1] === '0' ){
c = c.slice(0,c.length-1) ;
}
c = c.split('').reverse().join('') ;
return c ;
}