Limits, you must declare variables

type in C/C++ and Fortran2008 bits range
int/INTEGER (2) 16 -32768 to 32767
unsigned int 16 0 to 65535
signed int 16 -32768 to 32767
short int 16 -32768 to 32767
unsigned short int 16 0 to 65535
signed short int 16 \( -32768 \) to 32767
int/long int/INTEGER (4) 32 -2147483648 to 2147483647
signed long int 32 -2147483648 to 2147483647
float/REAL(4) 32 \( 3.4\times 10^{-44} \) to \( 3.4\times 10^{+38} \)
double/REAL(8) 64 \( 1.7\times 10^{-322} \) to \( 1.7\times 10^{+308} \)
long double 64 \( 1.7\times 10^{-322} \) to \( 1.7\times 10^{+308} \)