How to reverse the 4 bytes of an unsigned integer?
c, int, unsigned
Solution
Try this:
int getal; // original number
int reversed; // 4 bytes reversed of getal
/* get number form console here */
uint8_t *n1, *n2;
n1 = (uint8_t *) &getal;
n2 = (uint8_t *) &reversed;
n2[0] = n1[3];
n2[1] = n1[2];
n2[2] = n1[1];
n2[3] = n1[0];
/* print reversed here */
Problem
I am trying to reverse the unsigned integer by using the '«' and '»', and bitwise 'AND' and 'OR' (& and |), but can't figure out how to do this. What I already have; ``` int main(int argc, char** argv) { unsigned int getal; scanf("%i", &getal); printf("%X\n", getal); return 0; } ``` User input: 0xaabbccdd, output now: AABBCCDD, what it should output DDCCBBAA I also tried; ``` int main(int argc, char** argv) { unsigned int getal; unsigned int x; scanf("%i", &getal); int i; for (i = 0; i < 32; ++i) { getal <<= 1; getal |= (x & 1); x >>= 1; printf("%X\n", getal); } return 0; } ``` but the result was completely different.