c++ - Operator >> doesn't like vector<bool>? -

i have following code takes vector , writes file, , opens file , writes content different vector.

#include <fstream> #include <iostream> #include <vector>  using namespace std;  int main() {     vector<bool> q, p; //         ^^^^     q.resize(5, 0);     q[0] = 1;     q[2] = 1;     q[4] = 1;      ofstream ofile("file.log");      (int = 0; i<5; i++)         ofile <<q[i]<<" ";      ofile.close();      ifstream ifile("file.log");      p.resize(5);      int = 0; //        vvvvvvvvvvvv     while(ifile>> p[i])     {         cout <<i<<"\t"<<p[i]<<endl;         i++;     }      ifile.close();      return 0; } 

what noticed code compiles , runs no problem when vector contains double, int, , long data types, produces error if changed bool. error message get:

../src/timeexample.cpp:31: error: no match ‘operator>>’ in ‘ifile >> p.std::vector<bool, _alloc>::operator[] [with _alloc = std::allocator<bool>](((long unsigned int)i))’ 

so, know why happens?

thank you

std::vector<bool> specialized have space efficiency. operator[] wouldn't able return addressable variable, returns std::vector<bool>::reference proxy object instead. input temporary variable , transfer it:

bool b; while (ifile >> b) {     p[i] = b;     cout <<i<<"\t"<<b<<endl;     i++; }