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Questions tagged [cout]

std::cout is the global stream object provided by the C++ standard library for writing to the standard output stream.

For more general questions about std::ostream use the or tags.

Bjarne Stroustrup, the creator of C++, explains that cout is pronounced "see-out" and the "c" stands for "character". (wcout is used for wide character output to the standard output stream)

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'printf' vs. 'cout' in C++

What is the difference between printf() and cout in C++?
hero
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How do I print a double value with full precision using cout?

In my earlier question I was printing a double using cout that got rounded when I wasn't expecting it. How can I make cout print a double using full precision?
Restore the Data Dumps
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How do I print out the contents of a vector?

How do I print out the contents of a std::vector to the screen? A solution that implements the following operator<< would be nice as well: template std::ostream &…
forthewinwin
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Error "undefined reference to 'std::cout'"

Shall this be the example: #include using namespace std; int main() { cout << "Hola, moondo.\n"; } It throws the error: gcc -c main.cpp gcc -o edit main.o main.o: In function `main': main.cpp:(.text+0xa): undefined reference to…
D1X
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How can I pad an int with leading zeros when using cout << operator?

I want cout to output an int with leading zeros, so the value 1 would be printed as 001 and the value 25 printed as 025. How can I do this?
jamieQ
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cout is not a member of std

I'm practicing using mulitple files and header files etc. So I have this project which takes two numbers and then adds them. Pretty simple. Here are my files: main.cpp #include #include "add.h" int main() { int x = readNumber(); …
Paul Hannon
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uint8_t can't be printed with cout

I wrote a simple program that sets a value to a variable and then prints it, but it is not working as expected. My program has only two lines of code: uint8_t a = 5; cout << "value is " << a << endl; The output of this program is value is , i.e.,…
CoderInNetwork
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C++ cout hex values?

I want to do: int a = 255; cout << a; and have it show FF in the output, how would I do this?
user34537
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How to print to console when using Qt

I'm using Qt4 and C++ for making some programs in computer graphics. I need to be able to print some variables in my console at run-time, not debugging, but cout doesn't seem to work even if I add the libraries. Is there a way to do this?
lesolorzanov
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Why I cannot cout a string?

Why I cannot cout string like this: string text ; text = WordList[i].substr(0,20) ; cout << "String is : " << text << endl ; When I do this, I get the following error: Error 2 error C2679: binary '<<' : no operator found which takes a…
Ata
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What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?

I tried researching the difference between cout, cerr and clog on the internet but couldn't find a perfect answer. I still am not clear on when to use which. Can anyone explain to me, through simple programs and illustrate a perfect situation on…
Arlene Batada
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How to make C++ cout not use scientific notation

double x = 1500; for(int k = 0; k<10 ; k++){ double t = 0; for(int i=0; i<12; i++){ t += x * 0.0675; x += x * 0.0675; } cout<<"Bas ana: "<
Yunus Eren Güzel
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C++ printing boolean, what is displayed?

I print a bool to an output stream like this: #include int main() { std::cout << false << std::endl; } Does the standard require a specific result on the stream (e.g. 0 for false)?
user788171
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'cout' was not declared in this scope

I have a C++ program: test.cpp #include int main() { char t = 'f'; char *t1; char **t2; cout<
user494461
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how do I print an unsigned char as hex in c++ using ostream?

I want to work with unsigned 8-bit variables in C++. Either unsigned char or uint8_t do the trick as far as the arithmetic is concerned (which is expected, since AFAIK uint8_t is just an alias for unsigned char, or so the debugger presents it. The…
Nathan Fellman
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