‘const int’ vs. ‘int const’ as function parameters in C++ and C

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The trick is to read the declaration backwards (right-to-left):

const int a = 1; // read as "a is an integer which is constant"
int const a = 1; // read as "a is a constant integer"

Both are the same thing. Therefore:

a = 2; // Can't do because a is constant

The reading backwards trick especially comes in handy when you’re dealing with more complex declarations such as:

const char *s;      // read as "s is a pointer to a char that is constant"
char c;
char *const t = &c; // read as "t is a constant pointer to a char"

*s="A"; // Can't do because the char is constant
s++;      // Can do because the pointer isn't constant
*t="A"; // Can do because the char isn't constant
t++;      // Can't do because the pointer is constant

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