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#include <stdio.h>
#define INT_NBITS 32
unsigned getbits(unsigned x, int from, int to);
void pbits(int x);
unsigned setbits(unsigned x, int from, int to, int source);
int
main(void)
{
int x = 423834583;
int y = 354543434;
pbits(x);
pbits(y);
pbits(setbits(x, 12, 5, y));
return 0;
}
unsigned
getbits(unsigned x, int from, int to)
{
return (x >> (from+1-to)) & ~(~(unsigned)0 << to);
}
void
pbits(int x)
{
for (int i = INT_NBITS-1; i >= 0; i--) {
if (i%4 == 3)
printf(" ");
printf("%u", getbits(x, i, 1));
}
printf("\n");
}
unsigned
setbits(unsigned x, int from, int to, int source)
{
int model = ((((unsigned)~0 << (INT_NBITS-from)) >> (INT_NBITS - (from+to))) << to);
return (x & ~model) | (source & model);
}
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