UVa 263 Number Chains

 1  #include <stdio.h>

 2  #include <stdlib.h>

 3  #include <algorithm>

 4  #include <iostream>

 5  #include <string.h>

 6  #include <string>

 7  #include <set>

 8  using namespace std;

 9  int main()

10  {

11      string str;

12      while(cin>>str && str[0]!='0')

13      {

14          int start=atoi(str.c_str());

15          set<int> ss;

16          int coun=0;

17          printf("Original number was %s\n",str.c_str());

18          int ans=0,pre=-10000000,c=0;

19          while(1)

20          {

21              string second=str;

22              sort(second.begin(),second.end());

23              string first=second;

24              reverse(first.begin(),first.end());

25              int f=atoi(first.c_str()),s=atoi(second.c_str());

26              ans=f-s;

27              printf("%d - %d = %d\n",f,s,ans);

28              c++;

29              ss.insert(ans);

30              if(coun==ss.size()) break;

31              coun=ss.size();

32              if(ans==pre) break;

33              pre=ans;

34              char tmp[15];

35              sprintf(tmp,"%d",ans);

36              str=tmp;

37          }

38          printf("Chain length %d\n\n",c);

39      }

40      return 0;

41  }