1038 Recover the Smallest Number

Given a collection of number segments, you are supposed to recover the smallest number from them. For example, given { 32, 321, 3214, 0229, 87 }, we can recover many numbers such like 32-321-3214-0229-87 or 0229-32-87-321-3214 with respect to different orders of combinations of these segments, and the smallest number is 0229-321-3214-32-87.

Input Specification:

Each input file contains one test case. Each case gives a positive integer N (≤104) followed by N number segments. Each segment contains a non-negative integer of no more than 8 digits. All the numbers in a line are separated by a space.

Output Specification:

For each test case, print the smallest number in one line. Notice that the first digit must not be zero.

Sample Input:

5 32 321 3214 0229 87

Sample Output:

22932132143287

代码长度限制

16 KB

时间限制

200 ms

内存限制

64 MB

• 代码

  #include
  #include
  #include
  #include
  #include
  #include
  using namespace std;
  string s[10001];
  **bool cmp(string a, string b)
  {
      return a + b < b + a;
  }**
  int main(){
      int n;
      cin >> n;
      for(int i = 0; i < n; i ++)
      {
          cin >> s[i];
      }
      sort(s, s + n, cmp);
      string resstr;
      for(int i = 0; i < n; i++)
      {
          resstr += s[i];
      }
      while(resstr.length() != 0 && resstr[0] == '0')
      {
          **resstr.erase(resstr.begin());**
      }
      if(resstr.length() == 0) cout << 0;
      cout << resstr;
      return 0;
  }
  
  

• 总结

  这题的主要思路是从柳神那看的，果然很妙，主要在于cmp函数的应用和string的一些方法。