The difference in the following areas:
First, the definitions:
1, int data type is an integer used to define the integer type.
2, float single-precision floating-point, accurate to six decimal places.
3, double double-precision floating-point type, can be accurate to the decimal point are twelve.
4, char for the character, data for defining the character type.
Second, the memory occupied:
1, int memory size is 4 byte.
2, float memory size is 4 byte.
3, double the memory size is 8 byte.
4, char memory size is 1 byte.
Elementary data type table is as follows:
Third, the data of the range indicated:
1, int: number range is - (the 31 th -12) to (-12 power of 31), number of -2147483647 2147483647 ~.
2, double: 1.111111111111111111111 range indicated as + 1023 * 2 ^ (1 1 52 later.) 1.7 * 10 ^ 308. Negative versa.
3, float: integer limit is 3.4 * 10 ^ 38, negative versa.
4、char：-128- 127。