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one's complement is a bitwise complement of a binary number. (ie, 1 becomes 0 and 0 becomes 1)
A one's complement isn't really used as much as a two's complement.
A two's complement is used in a system where the larges bit in a binary number represents a negative number. so the bits for a 4 bit number would have the values of (from right to left):
-8, 4, 2, 1
this allows you to represent any number from -8 (1000) to positive 7 (0111)
To find the two's complement of a number, you take the one's complement, and then add 1.
This significant because if a computer wants to subtract two numbers, it simply takes the two's complement of the second number and adds them together.
More significance arises in digital circuits when constructing circuits using only nand/nor gates, as these perform slightly faster than and/or gates.
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How do you write a program to determine whether a number is odd or even counter?
For positive integers, if the least significant bit is set then the number is odd, otherwise it is even. For negative integers in twos-complement notation, if the least significant bit is set then the number is odd, otherwise it is even. Twos-complement is the normal notation, allowing a range of -128 to +127 in an 8-bit byte. For negative integers in ones-complement notation, if the least significant bit is set then the number is even, otherwise it is odd. Ones-complement is less common, allowing a range of -127 to +127 in an 8-bit byte, where 11111111 is the otherwise non-existent value -0 (zero is neither positive nor negative). Ones-complement allows you to change the sign of a value simply by inverting all the bits. Twos-complement is the same as ones-complement but we also add one. Thus the twos complement of 0 is 0 because 11111111 + 1 is 0 (the overflowing bit is ignored). 11111111 then becomes -1 rather than the non-existent -0.
Signed binary subtraction 000000111001-111010000101 equals 000110101110 right?
Wrong. You don't say whether you are using ones-complement notation or twos-complement notation, but in either case you'd be wrong. Your answer of 000110101110 is 430 decimal, but the correct answer is 435 or 436 depending on which notation you use. Ones-complement notation: 000000111001 - 111010000101 = 000110110011 Decimal equivalent: 57 - (-378) = 57 + 378 = 435 Twos-complement notation: 000000111001 - 111010000101 = 000110110100 Decimal equivalent: 57 - (-379) = 57 + 379 = 436 Note that in ones-complement, converting the sign of any value simply inverts all the bits. So if we invert 111010000101 we get 000101111010 which is 378, thus the original signed value was -378. In twos complement we invert all the bits (as per ones-complement) and add 1, so 000101111010 + 1 is 000101111011 is 379, thus the original signed value was -379. QED.
What is meant by ones-compliment of a decimal number?
One-complement applies to binary values, not decimal values. Therefore when we say the ones-complement of a decimal value we mean convert the value to binary, invert all the bits (the ones-complement), then convert the result back to decimal. For example, the decimal value 42 has the following representation in 8-bit binary: 00101010 If we invert all the bits we get 11010101 which is 213 decimal. Thus 213 is the ones-complement of 42, and vice versa. However, it's not quite as straightforward as that because some (older) systems use ones-complement notation to represent signed values, such that 11010101 represents the decimal value -42. The problem with this notation is that the ones-complement of 00000000 is 11111111 which means the decimal value 0 has two representations, +0 and -0 respectively. In the real-world, zero is neither positive nor negative. To resolve this problem, modern systems use twos-complement to represent signed values. The twos-complement of any value is simply the ones-complement plus one. Thus the ones-complement of 42 becomes -43, therefore the twos-complement of 42 is -43+1 which is -42. Thus -42 is represented by the binary value 11010110 in twos-complement notation. With twos-complement, there is only one representation for the value 0. This is because the ones-complement of 00000000 is 11111111 and if we add 00000001 we get 00000000. Note that we don't get 100000000 because the result cannot have any more bits than were in the original value. When an "overflow" occurs, we cycle back to zero. As a result, incrementing and decrementing signed values has exactly the same logic as incrementing or decrementing unsigned values and flipping the sign of any value is only slightly more complicated by the extra addition operation. However, flipping the sign of a value is a much rarer operation than counting so the cost is trivial compared to the cost of counting operations using ones-complement (because there are two values for zero). Note that ones-complement notation allows an 8-bit value to store signed values in the range -127 to +127, whereas twos-complement allows a range of -128 to +127 (through the elimination of the extra zero). But in unsigned notation, both allow the same range: 0 to 255. Although we rarely encounter ones-complement notation, it is important to keep in mind that not all systems use twos-complement notation, particularly when working with low-level but portable programming languages. This is the reason why both the C and the C++ standards state that the range of an 8-bit signed value is only guaranteed to store values in the range -127 to +127.
What is unsigned data types in turbo c?
The same as an unsigned type in any other implementation of C. An unsigned type is an integer that is guaranteed positive. Normally, the most-significant bit of an integer denotes the sign (positive or negative). Unsigned types use this bit to denote value, effectively doubling the range of positive values over that of the signed equivalent. For instance, a signed char has a guaranteed range of -127 to +127 while an unsigned char has a guaranteed range of 0 to 255. Note that a signed char typically has a valid range of -128 to +127, however this is only true on systems that utilise twos-complement notation. Those that use the older ones-complement notation have two representations for the value zero (one positive, one negative). Ones-complement simply inverts all the bits of a value to switch the sign of a value, whereas twos-complement adds the value 1 after inverting all the bits. The value zero is denoted as 00000000 in binary. Inverting the bits creates 11111111, which is minus zero on a ones-complement system and -1 on a twos-complement system. -1 + 1 is 0, hence we add 1 on a twos-complement system.
1's complement of 1000?
Ones complement simply switches the state of all the bits (0s becomes 1s and 1s becomes 0s). Assuming 1000 is binary (for decimal 8), the 1's complement would be 0111. But if 1000 is really decimal one thousand, the binary equivalent would 1111101000, thus the ones complement would be 0000010111. Ones complement was originally used to represent signed integers. To flip the sign, all bits were flipped and the most-significant bit denoted the sign (0 for positive, 1 for negative). The problem with one's complement is that we end with two representations for the value zero: 00000000 and 11111111 in 8-bit notation. To eliminate this, most modern systems now use twos complement, which is ones complement plus one. Thus 00000000 is 11111111 + 00000001 which is 00000000. Note that ones complement notation means that an 8-bit value has a valid range of -127 through +127 (with two representations for zero) while twos complement gives us a range of -128 through +127. Signed integer notation is also system-dependent, hence the reason why a char data type in C only has a guaranteed range of at least -127 through +127 across all implementations. For that reason it is not safe to assume that -128 has a valid representation in 8-bit signed notation across all implementations.
What is the number 0111111111111111 in twos complement?
100000000000001
How do you write a program to determine whether a number is odd or even counter?
For positive integers, if the least significant bit is set then the number is odd, otherwise it is even. For negative integers in twos-complement notation, if the least significant bit is set then the number is odd, otherwise it is even. Twos-complement is the normal notation, allowing a range of -128 to +127 in an 8-bit byte. For negative integers in ones-complement notation, if the least significant bit is set then the number is even, otherwise it is odd. Ones-complement is less common, allowing a range of -127 to +127 in an 8-bit byte, where 11111111 is the otherwise non-existent value -0 (zero is neither positive nor negative). Ones-complement allows you to change the sign of a value simply by inverting all the bits. Twos-complement is the same as ones-complement but we also add one. Thus the twos complement of 0 is 0 because 11111111 + 1 is 0 (the overflowing bit is ignored). 11111111 then becomes -1 rather than the non-existent -0.
Signed binary subtraction 000000111001-111010000101 equals 000110101110 right?
Wrong. You don't say whether you are using ones-complement notation or twos-complement notation, but in either case you'd be wrong. Your answer of 000110101110 is 430 decimal, but the correct answer is 435 or 436 depending on which notation you use. Ones-complement notation: 000000111001 - 111010000101 = 000110110011 Decimal equivalent: 57 - (-378) = 57 + 378 = 435 Twos-complement notation: 000000111001 - 111010000101 = 000110110100 Decimal equivalent: 57 - (-379) = 57 + 379 = 436 Note that in ones-complement, converting the sign of any value simply inverts all the bits. So if we invert 111010000101 we get 000101111010 which is 378, thus the original signed value was -378. In twos complement we invert all the bits (as per ones-complement) and add 1, so 000101111010 + 1 is 000101111011 is 379, thus the original signed value was -379. QED.
The twos complement of 11001101 is?
00110011 is the 2's complement for this unsigned number and 10110011 if this is a signed number
What is meant by ones-compliment of a decimal number?
One-complement applies to binary values, not decimal values. Therefore when we say the ones-complement of a decimal value we mean convert the value to binary, invert all the bits (the ones-complement), then convert the result back to decimal. For example, the decimal value 42 has the following representation in 8-bit binary: 00101010 If we invert all the bits we get 11010101 which is 213 decimal. Thus 213 is the ones-complement of 42, and vice versa. However, it's not quite as straightforward as that because some (older) systems use ones-complement notation to represent signed values, such that 11010101 represents the decimal value -42. The problem with this notation is that the ones-complement of 00000000 is 11111111 which means the decimal value 0 has two representations, +0 and -0 respectively. In the real-world, zero is neither positive nor negative. To resolve this problem, modern systems use twos-complement to represent signed values. The twos-complement of any value is simply the ones-complement plus one. Thus the ones-complement of 42 becomes -43, therefore the twos-complement of 42 is -43+1 which is -42. Thus -42 is represented by the binary value 11010110 in twos-complement notation. With twos-complement, there is only one representation for the value 0. This is because the ones-complement of 00000000 is 11111111 and if we add 00000001 we get 00000000. Note that we don't get 100000000 because the result cannot have any more bits than were in the original value. When an "overflow" occurs, we cycle back to zero. As a result, incrementing and decrementing signed values has exactly the same logic as incrementing or decrementing unsigned values and flipping the sign of any value is only slightly more complicated by the extra addition operation. However, flipping the sign of a value is a much rarer operation than counting so the cost is trivial compared to the cost of counting operations using ones-complement (because there are two values for zero). Note that ones-complement notation allows an 8-bit value to store signed values in the range -127 to +127, whereas twos-complement allows a range of -128 to +127 (through the elimination of the extra zero). But in unsigned notation, both allow the same range: 0 to 255. Although we rarely encounter ones-complement notation, it is important to keep in mind that not all systems use twos-complement notation, particularly when working with low-level but portable programming languages. This is the reason why both the C and the C++ standards state that the range of an 8-bit signed value is only guaranteed to store values in the range -127 to +127.
Does Binary numbers consist of ones and twos?
No, binary numbers don't consist of ones and twos, they are ones and zeros.
What does spinning on the ones and twos mean?
"ones and twos" refers to the two turntables commonly used by DJs. "Spinning on the ones and twos" then, is the act of playing (spinning) records on the turntables.
How do you programme Twos complement in binary in c?
int complement (int n) { return -n; } or int complement (int n) { return ~n+1; } both does the same thing.
Does a sum of infinite ones equal a sum of infinite twos?
Yes, the sum of infinite ones equal the sum of infinite twos.
What is unsigned data types in turbo c?
The same as an unsigned type in any other implementation of C. An unsigned type is an integer that is guaranteed positive. Normally, the most-significant bit of an integer denotes the sign (positive or negative). Unsigned types use this bit to denote value, effectively doubling the range of positive values over that of the signed equivalent. For instance, a signed char has a guaranteed range of -127 to +127 while an unsigned char has a guaranteed range of 0 to 255. Note that a signed char typically has a valid range of -128 to +127, however this is only true on systems that utilise twos-complement notation. Those that use the older ones-complement notation have two representations for the value zero (one positive, one negative). Ones-complement simply inverts all the bits of a value to switch the sign of a value, whereas twos-complement adds the value 1 after inverting all the bits. The value zero is denoted as 00000000 in binary. Inverting the bits creates 11111111, which is minus zero on a ones-complement system and -1 on a twos-complement system. -1 + 1 is 0, hence we add 1 on a twos-complement system.
What are factors of 1934 that add up to 80?
1854
What do you add to 1 five to make 4 twos?
3 ones
