removing last written symbol from stream

[Denis Petronenko]

Hello,

for(int i=0; i<100; ++i){
cout << i << ",";
}
// how can i remove last comma here?
......
cout << endl;

 

[mlimber]

Hello,

for(int i=0; i<100; ++i){
cout << i << ",";
}
// how can i remove last comma here?
.....
cout << endl;

Use an if statement in the for-loop. If you're on the last iteration,
don't print one.

Cheers! --M

 

[Denis Petronenko]

Use an if statement in the for-loop. If you're on the last iteration,
don't print one.

Cheers! --M

ok. lets see on following example.

i want to print elements of set divided by comma:

set<int> myset;
for(int i=0; i<10; ++i) myset.insert(random());
for_each(myset.begin(),myset.end(),printint());

i defined function object to do this job:

class printint
{
public:
printint(){}
~printint(){
// remove last comma here
cout << endl;
}

void operator()(int val){
cout << val << ",";
}
};

How can i remove or not write last comma here? function object don't
know how many elements stored in myset.

Thanks.

 

[Daniel T.]

Hello,

for(int i=0; i<100; ++i){
cout << i << ",";
}
// how can i remove last comma here?
.....
cout << endl;

Don't put it in in the first place.

for ( int i = 0; i < 99; ++i )
cout << i << ',';
cout << 99 << endl;

 

[mlimber]

ok. lets see on following example.

i want to print elements of set divided by comma:

set<int> myset;
for(int i=0; i<10; ++i) myset.insert(random());
for_each(myset.begin(),myset.end(),printint());

i defined function object to do this job:

class printint
{
public:
printint(){}
~printint(){
// remove last comma here
cout << endl;
}

void operator()(int val){
cout << val << ",";
}
};

How can i remove or not write last comma here? function object don't
know how many elements stored in myset.

Thanks.

You either need to find some other way to do it, or you need to make
the functor stateful (e.g., have it keep its own count and pass the
upper limit in via the constructor).

Cheers! --M

 

[=?ISO-8859-15?Q?Juli=E1n?= Albo]

i defined function object to do this job:

class printint
{
public:
printint(){}
~printint(){
// remove last comma here
cout << endl;
}

void operator()(int val){
cout << val << ",";
}
};

How can i remove or not write last comma here? function object don't
know how many elements stored in myset.

But it can know when it's first called. So you can supress the first instead
of the last.

if (first)
first= false;
else
cout << ",";
cout << val;