POJ.2100 Graveyard Design

1.Problem
http://poj.org/problem?id=2100

2.Idea
Two Pointers

3.Source

 ll S;  
 ll s, t;  
 int n = 10000000;  
 vector<int> ans1, ans2;  
 void solve()  
 {  
      int res = 0;  
      ll s = 0, t = 0;  
      ll sum = 0;  
      for (;;) {  
           while (t < n && sum < S) {  
                sum += t*t; t++;  
           }  
           if (sum < S) break;  
           if (sum == S) {  
                if (s == 0) s++;  
                ans1.push_back(s);  
                ans2.push_back(t - 1);  
           }  
           sum -= s*s;  
           s++;  
      }  
      printf("%d\n", ans1.size());  
      for (int i = 0; i < ans1.size(); i++) {  
           printf("%d", ans2[i] - ans1[i] + 1);  
           for (int j = ans1[i]; j <= ans2[i]; j++) printf(" %d", j);  
           printf("\n");  
      }  
 }  
 int main()  
 {  
      scanf("%lld", &S);  
      n = sqrt(1.0 * S) + 1;  
      solve();  
      return 0;  
 }