Use of stream iterator

10.29 write a program and use the stream iterator to read a text file and store it in a string in a vector.

#include<iostream>#include<vector>#include<fstream>#include<string>#include<iterator>using namespace std;int main(){    ifstream in("1.txt");    istream_iterator<string> in_iter(in),eof;    ostream_iterator<string> out_iter(cout," ");    vector<string> vec;    while(in_iter!=eof)        vec.push_back(*in_iter++);    for(auto v:vec)        out_iter=v;    cout<<endl;    return 0;}

 

10.30 use stream iterator, sort, and copy to read an integer sequence from the standard input, sort it, and write the result to the standard output.

#include<iostream>#include<vector>#include<fstream>#include<iterator>#include<algorithm>using namespace std;int main(){    istream_iterator<int> in_iter(cin),eof;    ostream_iterator<int> out_iter(cout," ");    vector<int> vec;    while(in_iter!=eof)        vec.push_back(*in_iter++);    sort(vec.begin(),vec.end());    copy(vec.begin(),vec.end(),out_iter);    cout<<endl;    return 0;}

 

10.33 write a program and accept three parameters: one input file and two output file names. The input file must be an integer. Use istream_iterator to read text input files. Use ostream_iterator to write odd numbers to the first output file. Each value is followed by a space. Writes an even number to the second output file. Each value occupies an exclusive row.

#include<iostream>#include<vector>#include<fstream>#include<iterator>using namespace std;int main(){    ifstream in("1.txt");    ofstream out1("2.txt");    ofstream out2("3.txt");    istream_iterator<int> in_iter(in),eof;    ostream_iterator<int> out_iter1(out1," ");    ostream_iterator<int> out_iter2(out2,"\n");    vector<int> vec;    while(in_iter!=eof)        vec.push_back(*in_iter++);    for(auto v:vec)    {        if(v%2)          out_iter1=v;        else          out_iter2=v;    }    cout<<endl;    return 0;}