Leetcode: Text Justification

Text Justification.cpp

class Solution {
public:
	vector<string> fullJustify(vector<string> &words, int L) {
		int N = words.size();  vector<string> ans;
		for (int i = 0; i < N;) {
			int n = 1;  int len = words[i].size();
			for (int j = i+1; j < N; ++j) {
				if (len + words[j].size() + 1 > L) break;
				len += words[j].size() + 1;
				++n;
			}
			if (i+n < N) { // not last line.
				string line;
				if (n > 1) { // at least two words
					int sp = (L-len)/(n-1);
					int ex_sp = (L-len)%(n-1);
					string space(sp, ' ');
					for (int k = i; k < i+n-1; ++k) {
						line += words[k] + ' ' + space;
						if (ex_sp) {
							line += ' ';
							--ex_sp;
						}
					}
					line += words[i+n-1];
				} else if (n==1) {  // one word
					line += words[i]+string(L-len, ' ');
				}
				ans.push_back(line);
			} else { // last line
				int sp = L - len;  string line;
				for (int k = i; k < i+n-1; ++k) line += words[k] + ' ';
				line += words[i+n-1] + string(sp, ' ');
				ans.push_back(line);
			}
			i+=n;
		}
		return ans;
	}
};

i: 当前行的第一个单词的下标
n: 当前行总共塞得下几个单词(从words[i]开始);
len: 从words[i]开始的n个单词+n-1个空格的长度

40行有点长了, 还没有看diccuss, 感觉不知道如何才能写得更简洁了.

因为一个typo : k < i+n-1打成了 i < i+n-1找了许久. 果然流程每一步均不可废.