How to convert integer to hexadecimal in C?

Question

How to convert integer to hexadecimal in C?

Answer 1

Usually with printf (or one of its cousins) using the %x format specifier. Alternatively, strtol specifying the base as 16.

Answer 2

http://en.wikipedia.org/wiki/Hexadecimal + http://www.cplusplus.com/reference/clibrary/cstdio/printf/ + http://www.cplusplus.com/doc/hex/ + http://en.wikipedia.org/wiki/Integer . Those should give you all the information you'll ever need about integers, bases and converting between bases in C.

Answer 3

This code

int a = 5;
printf("%x\n", a);

prints

5

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This code

int a = 5; 
printf("0x%x\n", a);

prints

0x5

---

This code

int a = 89778116;
printf("%x\n", a);

prints

559e7c4

---

If you capitalize the x in the format it capitalizes the hex value:

int a = 89778116;
printf("%X\n", a);

prints

559E7C4

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If you want to print pointers you use the p format specifier:

char* str = "foo";
printf("0x%p\n", str);

prints

0x01275744