#include <stdio.h>
#include <stdint.h>
uint32_t clear_bits(uint32_t reg, uint8_t pos, uint8_t len) {
// Your code here
uint32_t bitmask=1<<pos;
for(int i=1;i<len;i++){
bitmask+=1<<pos+i;
}
return (~(bitmask))®
}
int main() {
uint32_t reg;
uint8_t pos, len;
scanf("%u %hhu %hhu", ®, &pos, &len);
printf("%u", clear_bits(reg, pos, len));
return 0;
}