1.The code defines the variables as unsigned integer however the output is shown negative.
#include<stdio.h>
#include<limits.h>
#include<stdint.h>
int main(){
uint32_t a= 25,b=50;
a = a-b;
printf("\n%d\n",a);
return 0;
}
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GANESH B K
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It's because you told `printf` to print a `%d`, which is a signed integer. That's what `%d` means. A computer always does exactly what you tell it to do, instead of what you want it to do. – Sam Varshavchik Jan 26 '18 at 03:56
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The correct format specifier would be (The macro PRIu32 is defined in inttypes.h header ).
printf("%" PRIu32 "\n",a);
%d expects the arguments passed to it would be address of an signed int - that's why the value you passed is considered as signed int. After you have used the correct format specifier the output would be UINT32_MAX+1-25.
Using the wrong format specifier is undefined behavior.
user2736738
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It may be worth adding that the `PRIu32` macro is defined in the `inttypes.h` header file. – ad absurdum Jan 26 '18 at 04:03
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