查人人中国名人网岗位粉尘监测标准:求助各位C++的Professor，编写一个简练的C++程序（急需）
来源：百度文库 编辑：查人人中国名人网 时间：2024/05/07 07:12:49
Write a program to ask user to enter a filename for reading . Read the lines in the file and display the longest line on the screen with corresponding line number.
#include<iostream>
#include<fstream>
#include<string>
using namespace std;
int main( ) {
cout << "Please enter the name of the file to be read: ";
string fname;
cin >> fname;
ifstream in( fname.c_str( ) );
if( ! in ) {
cout << "Error: File not found or can't be read.\n";
return 1;
}
string s;
getline( in, s );
string longest = s;
int lineNum = 1;
int line = 2;
while( getline( in, s ) ) {
if( longest.size( ) < s.size( ) ) {
longest = s;
lineNum = line;
}
++line;
}
cout << "The longest line is line number " << lineNum << ":\n"
<< longest << endl;
return 0;
}