TCHS SRM 53 250 pt - DNAConstruction solution

TCHS SRM 53 250 pt - DNAConstruction: http://community.topcoder.com/stat?c=problem_statement&pm=9818&rd=13486

TCHS SRM 53 250 pt - DNAConstruction editorial:  http://community.topcoder.com/tc?module=Static&d1=hs&d2=match_editorials&d3=hs_srm53

TCHS SRM 53 250 pt - DNAConstruction solution: 

#include <iostream>
#include <cstring>
#include <algorithm>

class DNAConstruction {
 public: int maxLength(std::string n) {
  int a=0, t=0, c=0, g=0, tot=0;
  for(int i=0; i<n.length(); i++) {
   if(n[i]=='A') a++;
   else if(n[i]=='T') t++;
   else if(n[i]=='C') c++;
   else if(n[i]=='G') g++;
  }
  tot=std::min(a, t) + std::min(c, g);
  return tot;
 }
};

for proper use of "min" and "max" in c++:

1 - http://www.cplusplus.com/reference/algorithm/max/

2 - http://stackoverflow.com/questions/1632145/use-of-min-and-max-functions-in-c


and for iterating through string in c++: http://stackoverflow.com/questions/1315041/how-can-i-iterate-through-a-string-and-also-know-the-index-current-position