您好,登錄后才能下訂單哦!
38. Count and Say
The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...
1
is read off as "one 1"
or 11
.11
is read off as "two 1s"
or 21
.21
is read off as "one 2
, then one 1"
or 1211
.
Given an integer n, generate the nth sequence.
Note: The sequence of integers will be represented as a string.
根據(jù)規(guī)律可以寫出后面的:
1. 1
2. 11
3. 21
4. 1211
5. 111221
6. 312211
7. 13112221
8. 1113213211
9. 31131211131221
10. 13211311123113112211
思路:
1.用2個(gè)串來(lái)替換存儲(chǔ)記錄result,tmp。
2.記錄當(dāng)前值n,獲取當(dāng)前值最大連續(xù)長(zhǎng)度m。
3.tmp串追加"m",再追加"n"。
代碼如下:
class Solution { public: string countAndSay(int n) { if (--n < 0) return ""; string result = "1"; string tmp; //臨時(shí)串 int step = 1;//步長(zhǎng) char cur; //當(dāng)前元素 while (n) { cur = result[0]; for (int i = 0; i < result.size(); i++) { if ( i+1 < result.size() && result[i] == result[i + 1]) { step++; } else { stringstream stepStream; stepStream << step; string stepStr = stepStream.str(); tmp.append(1,stepStr[0]); tmp.append(1,cur); step = 1; cur = result[i + 1]; } } swap(result, tmp); tmp = ""; n--; } return result; } };
2016-08-10 17:24:26
免責(zé)聲明:本站發(fā)布的內(nèi)容(圖片、視頻和文字)以原創(chuàng)、轉(zhuǎn)載和分享為主,文章觀點(diǎn)不代表本網(wǎng)站立場(chǎng),如果涉及侵權(quán)請(qǐng)聯(lián)系站長(zhǎng)郵箱:is@yisu.com進(jìn)行舉報(bào),并提供相關(guān)證據(jù),一經(jīng)查實(shí),將立刻刪除涉嫌侵權(quán)內(nèi)容。