Why is memset() incorrectly initializing int?

Question

Why is the output of the following program 84215045?

int grid[110];
int main()
{
    memset(grid, 5, 100 * sizeof(int));
    printf(\"%d\", grid         


        

Answer 1

memset(grid, 5, 100 * sizeof(int));

You are setting 400 bytes, starting at (char*)grid and ending at (char*)grid + (100 * sizeof(int)), to the value 5 (the casts are necessary here because memset deals in bytes, whereas pointer arithmetic deals in objects.

84215045 in hex is 0x05050505; since int (on your platform/compiler/etc.) is represented by four bytes, when you print it, you get "four fives."