visual studio 2013 - Displaying the ASCII characters in C without unsigned char - 


unsigned char a;  for(a=32;a<128;a=a+1) printf("%d='%c'\t",a,a); return(0);

why have put unsigned char? when left char, executed program , giving me infinite loop. shouldn't stop when a=127?

char means either signed or unsigned depends on implementation. makes behaviour of code implementation defined.
seems on machine signed. minimum , maximum value of signed char -127 & +127 respectively per c standard. value greater 127 or less -127 can't assigned a otherwise invoke undefined behaviour.

after a reaches 127, incremented 1 , value becomes 128 can't hold signed char variable , hence code invokes undefined behaviour.


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