How can I store a large integer value in a variable of C ? If i am declaring a with int a; it won't work. I have used this with long long int.It is not working.
if( a>=0 && a <= (1000000000000000000)) What to declare variable a so that it will not so any error.It should be integer.
Compiler error integer constant is too large for long type. 3 Answers
Try a unsigned long long, assuming the value is positive, it can hold up to
18,446,744,073,709,551,615 (VS 13) However, you must use the ULL syntax.
Lets look at this if statement you wrote:
if( a>=0 && a <= (1000000000000000000)) 1000000000000000000 is too big for an integral literal so you will need a bigger literal type. You should declare a as an int64_t and do the comparion like that:
if( a>=INT64_C(0) && a <= INT64_C(1000000000000000000)) Note that this will only work in a C99 or C++11 compiler when you #include <cstdint> or #include <stdint.h>
Edit: in current draft of the standard you can find this sentence (2.14.2/2):
The type of an integer literal is the first of the corresponding list in Table 6 in which its value can be represented.
It means that compiler should use the required literal type automatically to make your literal fit. Btw I didn't see that kind of compiler.
1You can use a long long to store this integer. A long long is guranteed to hold at least 64 bits.
The problem with this code: if( a>=0 && a <= (1000000000000000000)) is that you need to give the literal (1000000000000000000) the suffix LL if you want it to be of type long long or ULL for unsigned long long.
