[leetcode]394. Decode String -- JavaScript 代码

雨点打透心脏的1/2处 2022-09-25 12:17 14阅读 0赞

使用了两个栈，一个保存字符串，一个保存重复次数。

/** * @param {string} s * @return {string} */
    var decodeString = function(s) {
        String.prototype.repeat = function(n){
            var _this = this;
            var result = '';
            for(var i=0;i<n;i++) {
                result += _this;
            }
            return result;
        };
        var len = s.length;
        var stack = [];
        var readytp = 1;
        var strstack = [];
        var count = 0;
        var ret = "";
        for(var i=0;i<len;i++){
            var cur = s.charAt(i);
            if(Number(cur) || Number(cur)===0){
                if(readytp){
                    stack.push(0);
                    readytp = 0;
                }
                repeatnum = stack[stack.length-1];
                repeatnum = repeatnum *10 + Number(cur);
                stack[stack.length-1] = repeatnum;
                //console.log(stack);
            }else{
                readytp = 1;
                if(cur == "["){
                    count++;
                    strstack.push('');
                    continue;
                }
                if(cur == "]"){
                    count--;
                    var str = strstack.pop();
                    var num = stack.pop();
                    str = str.repeat(num);
                    count===0?ret += str:strstack[strstack.length-1]+=str;
                    continue;
                }
                count===0?ret+=cur:strstack[strstack.length-1] += cur;
            }
        }
        return ret;
    };