OJ Board

How to skip lines while using cin << ??

for example:

1
2
3

i want to read 3 and skip 1 and 2.

How to do this??

[cpp]string tmp;
for(int i=0;i< ...; ++i)getline(cin,tmp);
[/cpp]
It will skip a given number of lines.

... but be careful if you want to skip lines after using cin << ..., because there is still a newline left.

It might be a good idea - whenever there is a need to read a whole line - to read all lines in whole and then getting the values with istringstream or sscanf, then there is no need to worry about newlines that might or might not have been read.

I'll simply write:
[cpp]int n, dummy;
cin >> dummy >> dummy >> n;
[/cpp]

void skipline(int n)
{
int i,temp;
for(i=0;i<n;i++)cin>>temp;
}

This function skips line.Paramiter n is the number of skip lines.
Thanks

TISARKER wrote:void skipline(int n)
{
int i,temp;
for(i=0;i<n;i++)cin>>temp;
}

This function skips line.Paramiter n is the number of skip lines.
Thanks

It only works for single-integer lines. If the line has an alphabetic word, or more than one values, this will fail to do what you intended.

The right way, use:

[cpp]
#include <iostream>
#include <string>

const size_t num_lines_to_skip=2;
std::string s;

for (size_t i=0;i<num_lines_to_skip;++i)
std::getline(cin,s);
[/cpp]

int main()
{
int n;
cin.ignore(4); // '1' + '\n' + '2' + '\n' = 4 chars
cin>>n;
cout<<n<<endl; // output: 3
}