Question

write a function in C that swaps every other byte: for example,

Input: "badcfe”

Output: abcdef

I was thinking something like , where len would be two since I just want to swap values next to each other, but this doesnt work.

void

swap(char *p, int len) {

int i;

char tmp;

for(i = 0; i < len/2; i++) {

tmp = p[len-i-1];

p[len-i-1] = p[i];

p[i] = tmp;

}

}

Answer 1

void swap(char *p, int len) {
    int i;
    char tmp;
    for(i = 0; i < len && i+1 < len; i+=2) {
        tmp = p[i];
        p[i] = p[i+1];
        p[i+1] = tmp;
    }
}