#include <stdio.h>
 
int main(void) {
 
int i;
int xor = 0;
int b;
// $GPGLL,,,,,,V,N*64
 
char Received[18]= {'$','G','P','G','L','L','500.789',',',',',',',',',',','V',',','N','*','6','5'};
int loop;
 
// display array
for(loop = 0; loop < 18; loop++)
  printf("%c", Received[loop]);
  printf("%c\n ");
 
 
for(int i = 1; i<=14; i++)
	xor ^= Received[i];
	printf("%#02x  ", xor);
	printf("%d ", xor);
 
	b = ((Received[16]-'0') *16) + Received[17]-'0';
	printf("%d ", b);
 
if(xor == b){
	printf("WORKING!");
}
else{
	printf("not working");
}
 
return 0;
}

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