error: expected unqualified-id before numeric constant with boost library [closed]

hi guys i just installed boost libraries and built them and linked them to code:: blocks so in order to check if everything is working out I wrote a simple code to check for the existence of a text file . however, there is a strange error that I encountered i think it is related to the "boost" keyword cause the error happens in only the lines that contain "boost"

  #include <iostream>
#include <string>
#include<boost/filesystem.hpp>
using namespace std;

int main () {

cout<<"hello people , please help me out ."<<endl;

cout<<"test if \"d:\Array.txt\" exist"<<endl;
boost::filesystem::path 1_path("d:\Array.txt");

if(::filesystem::exists (1_path)){
    cout<<"the file exists !"<<endl;
}

}