Problem: 1405. Longest Happy String 最长快乐字符串耗时100%首先按照greedy的策略每次最多加两个字符优先队列拿到数量最多的字符不停的拼起来延迟放入pre先拿到cnt和ch再放入pre最后考虑到某个字符可能很多很多所以稀疏化找到其他连续的两个字符拆出来一个放到最后然后再次拼起来Codeusing pr pairint, char; class Solution { public: string longestDiverseString(int a, int b, int c) { priority_queuepr, vectorpr, decltype(lesspr()) pq; if(a 0) pq.push({a, a}); if(c 0) pq.push({c, c}); if(b 0) pq.push({b, b}); string tg; int cnt, mx; char ch, mxch; pr pre {-1, 0}; while(!pq.empty()) { cnt pq.top().first; ch pq.top().second; pq.pop(); if(pre.first 0) pq.push(pre); if(cnt 2) { tg ch; cnt-2; if(cnt 0) pre {cnt, ch}; else pre {-1, 0}; } else pre {-1, 0}; tg ch; } vectorchar tor {a, b, c}; cnt pre.first; ch pre.second; bool find; while(cnt 0) { find false; char hcr; int i; for(i 0; i tg.size(); i) { if(ch ! tg[i]) { if(i1 tg.size() tg[i1]tg[i]) { hcr tg[i]; find true; break; } } } if(!find) return tg; tg.erase(tg.begin() i); tg hcr; tg ch; cnt--; if(cnt 0) { tg ch; cnt--; } } return tg; } };