[Solved] when i do printf(“%d”,’=’+’=’);, why it is showing 122.Please explain in details

Question

In C, characters are represented internally using ascii. Characters are just numeric types, so adding them just adds the ascii* values. (Google ASCII for more info on this.)

In ascii, '=' is 61, so '=' + '=' is the same as 61 + 61, or 122, which is what you’re getting.

If you were hoping that + would concatenate a1 and a2, unfortunately that’s not the case, since chars are numeric values in C. If this is what you want, I’d google C strings (for how C handles strings) as a starting point.

If you were expecting it to do something else, I can edit my answer to explain that as well.

*EDIT: as pointed out by Fei Xiang, ASCII is not guaranteed by the C standard. However, on most modern systems, ASCII is used, and a similar answer to mine applies to your program regardless of the encoding used.

Accepted Answer

In C, characters are represented internally using ascii. Characters are just numeric types, so adding them just adds the ascii* values. (Google ASCII for more info on this.)

In ascii, '=' is 61, so '=' + '=' is the same as 61 + 61, or 122, which is what you’re getting.

If you were hoping that + would concatenate a1 and a2, unfortunately that’s not the case, since chars are numeric values in C. If this is what you want, I’d google C strings (for how C handles strings) as a starting point.

If you were expecting it to do something else, I can edit my answer to explain that as well.

*EDIT: as pointed out by Fei Xiang, ASCII is not guaranteed by the C standard. However, on most modern systems, ASCII is used, and a similar answer to mine applies to your program regardless of the encoding used.