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C Basics
C Basics
Sum, Difference, Increment, Decrement
Addition Operator (+)
The + operator adds the values on either side of it.
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You can also use variables in place of direct values.
Main.c
#include <stdio.h> int main() { int carsSold_2022 = 12; int carsSold_2023 = 45; int carsSold = carsSold_2022 + carsSold_2023; printf("Cars sold in two years: %d", carsSold); return 0; }
Note
While some programming languages allow you to concatenate strings using the
+operator, like "Hell" + "o" = "Hello", C does not.
Subtraction Operator (-)
The subtraction operator, -, calculates the difference between the values on either side of it.
Main.c
#include <stdio.h> int main() { int carsSold_2022_2023 = 200; int carsSold_2023 = 57; int carsSold_2022 = carsSold_2022_2023 - carsSold_2023; printf("Cars sold in 2022: %d", carsSold_2022); return 0; }
You can also use the - sign to convert positive values to their negative counterparts.
Main.c
#include <stdio.h> int main() { int value = 100; printf("Negative value: %d", -value); return 0; }
Increment Operator (++)
The increment operator, ++, was introduced to simplify code readability.
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This operator adds 1 to a value, and it's commonly used in loops. The example above illustrates the most basic use of the operator.
Decrement Operator (--)
Conversely, the decrement operator, --, subtracts 1 from a value:
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Pre vs. Post Increment
Increment and decrement operators come in two forms:
prefix (++a);
postfix (a++).
The distinction lies in the values they return:
| Operator | Usage | Description |
|---|---|---|
++ | a++ | Increments a by 1 but returns its original value |
++ | ++a | Increments a by 1 and returns its incremented value |
-- | --a | Decreases a by 1 and returns its decremented value |
-- | a-- | Decreases a by 1 but returns its original value |
Main.c
#include <stdio.h> int main() { int a = 5, b = 5; // a is increased to 6 // Then, it is displayed. printf("Prefix form a: %d\n", ++a); printf("a = %d\n", a); // 5 is displayed // Then, b is increased to 6. printf("Postfix form b: %d\n", b++); printf("b = %d\n", b); return 0; }
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