如何用stl算法计算vecotr中元素位置

转载自:http://topic.csdn.net/u/20100706/14/532c4158-e8ba-4378-9673-f9ca6fd7982b.html

    int GetParamIndex(std::string bankid)
    {
        vector<TBankItem>::iterator iter;
        TBankItem *item;
        int i=0;
        for(iter = begin();iter != end(); ++iter,++i)
        {
            item = &(*iter);
            if (item->BankID == bankid)
                return i;
        }
        return -1;
    }

如上面函数,是自己遍历了整个vector,有什么方式可以不自己遍历,而用stl算法实现该功能呢?

// find example
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;

int main () {
  int myints[] = { 10, 20, 30 ,40 };
  int * p;

  // pointer to array element:
  p = find(myints,myints+4,30);
  ++p;
  cout << "The element following 30 is " << *p << endl;

  vector<int> myvector (myints,myints+4);
  vector<int>::iterator it;

  // iterator to vector element:
  it = find (myvector.begin(), myvector.end(), 30);
  ++it;
  cout << "The element following 30 is " << *it << endl;

  return 0;
}

Output:
The element following 30 is 40The element following 30 is 40 

class A
{
   public:
      string str;
};
bool comp(const A& a, const string& str)
{
  return a.str == str;
}
int getIndex(vector<A>& vec, string& str)
{
  vector<A>::const_iterator it = find_if(vec.begin(), vec.end(), bind2th(comp, str));
   if ( it== vec.end()) return -1;
  return distance(vec.begin(), it);
}

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