UVA - 136

//set.count() //queue #include<iostream> #include<cstdio> #include<sstream> #include<cmath> #include<cctype> #include<cstring> #include<algorithm> #include<vector> #include<set> #include<map> #include<queue> #include<deque> #include<stack> using namespace std; #define ll long long priority_queue<ll,vector<ll>,greater<ll> > que; set<ll> st; int q[]={2,3,5}; int main(){ que.push(1); st.insert(1); int cnt=0; while(1){ ll a=que.top(); que.pop(); cnt++; if(cnt==1500){ printf("The 1500'th ugly number is %lld.\n",a); break; } for(int i=0;i<3;i++){ ll b=a*q[i]; if(!st.count(b)){ st.insert(b); que.push(b); } } } return 0; }