unsigned int to significant number

Question

Hello I am working on a project. Get unsigned 16 bit numbers and average them. No problem with getting average but when I tried to print to the screen, it prints meaningless symbols. So I figured out that I must convert it to decimal. Vs2015 converts it but I want to do it myself because my code is for a microprocessor. Here is my simulation...

int main(){

uint32_t  x = 0x12345678;
unsigned char c[4];

c[0] = x >> 24;// least significant 
c[1] = x >> 16;
c[2] = x >> 8;
c[3] = x;   // most significant
cout << x << endl;
cout << c[0] << endl;
cout << c[1] << endl;
cout << c[2] << endl;
cout << c[3] << endl;
system("pause");
return 0;

}

Output:

Try `cout << (int)c[0] << endl;` instead of `cout << c[0] << endl;`. Or, `cout << +c[0] << endl;`. — Daniel Langr, Jan 24 '20 at 08:05
In the ASCII character set, a character with value `0x12` is a line feed, a character with value `0x34` is the character `'4'`, a character with value `0x56` is the character `'V'`, and the character with value `0x78` is a `'x'`. Compare that observation with the output you are getting. — Peter, Jan 24 '20 at 08:10
sidenote: this code is platform-depended, check big endian and little endian — Andrew Kashpur, Jan 24 '20 at 08:20

Armin Montigny · Answer 1 · 2020-01-24T08:16:38.460

1

The problem here is, that the inserter operator << will treat char variables as character and not as a number. So, if the char variable contains 65, it will not print 65 but 'A'.

You need to convert the value to an unsigned int.

So:

std::cout << static_cast<unsigned int>(c[0]) << "\n";

Then it will give you the expected output.

edited Jan 24 '20 at 08:16

answered Jan 24 '20 at 08:10

Armin Montigny

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You should cast to an `unsigned int` instead – Fareanor Jan 24 '20 at 08:14
To print the hex value you will rather do it this way: `std::cout << hex << static_cast(c[0]) << "\n";` – EUS Jan 24 '20 at 08:15

unsigned int to significant number

1 Answers1