2-6

2-6.c

#include <stdio.h>

int unsigned setbits(unsigned x, int p, int n, unsigned y);

int main(){
  int x = 0b001110;
  int y = 0b0000000;
  int val = setbits(x, 3, 3, y);
  printf("%d\n", val);
// answer 0b0000111 -> 7;
}

int unsigned setbits(unsigned x, int p, int n, unsigned y){
  y = (y & ~(~0 << n)) + ((x >> (p - (n - 1))) & ~(~0 << n));
  return y;
}