64 lines
1.9 KiB
C
64 lines
1.9 KiB
C
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/*
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* C Program to Replace Bits in Integer x from Bit Position a to b from another Integer y
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*/
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#include <stdio.h>
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void changebits(int, int, int, int);
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int main()
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{
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int num1, num2, pos1, pos2;
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printf("**Replacing the bits in integer x from bit position a to b from another integer y**\n");
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printf("read number 1\n");
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scanf("%x", &num1);
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printf("Read number 2:\n");
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scanf("%x", &num2);
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printf("Read LSB postion:\n");
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scanf("%d", &pos1);
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printf("MSB should always be greater than LSB\n");
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printf("Read MSB position:\n");
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scanf("%d", &pos2);
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changebits(num1, num2, pos1, pos2);
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return 0;
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}
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/*Function to swap bits in given positions*/
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void changebits(int num1, int num2, int pos1, int pos2)
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{
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int temp1, temp_1, buffer2, bit1 = 0, bit2 = 0, counter = 0, a = 1;
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temp1 = num1;
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temp_1 = num1;
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buffer2 = num2;
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for (; pos1 <= pos2; pos1++)
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{
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a = 1;
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num1 = temp_1;
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num2 = buffer2;
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while (counter <= pos1)
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{
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if (counter == pos1)
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bit1 = (num1&1); //placing the bit of position 1 in bit1
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counter++;
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num1>> = 1;
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}
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counter = 0;
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while (counter <= pos1)
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{
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if (counter == pos1)
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bit2 = (num2&1); //placing the bit of position 2 in bit2
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counter++;
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num2 >>= 1;
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}
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counter = 0;
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if (bit1 == bit2);
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else
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{
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while (counter++<pos1)
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a = a << 1;
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temp1 ^= a; //placing the repplaced bit integer into temp1 variable
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}
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counter = 0;
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}
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printf("the number num1 after shifting the bits is 0x%x\n", temp1);
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}
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