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C Operators

Operators are symbols that act on one or more operands to produce a new value, and C groups them into categories -- arithmetic, relational, and logical -- based on the kind of result they produce.

What are Operators?

An operator is a special symbol that performs an operation on one or more values, called operands, producing a new value -- the + symbol, for example, adds two numeric operands together.

Example: What are Operators?

c
#include <stdio.h>
int main() {
	int sum = 3 + 4;
	printf("%d", sum);
	return 0;
}

Categories of Operators in C

C groups operators into categories based on what kind of result they produce: arithmetic operators compute numbers, relational operators compare values, and logical operators combine truthy or falsy results.

Example: Categories of Operators in C

c
#include <stdio.h>
int main() {
	int sum = 3 + 4;
	int isGreater = sum > 5;
	int result = (sum > 5) && (sum < 10);
	printf("%d %d %d", sum, isGreater, result);
	return 0;
}

Operators and Operands

Every operator acts on operands -- most operators like + and * are binary and need two operands, while a few like ++ and unary - are unary and act on just a single operand.

Example: Operators and Operands

c
#include <stdio.h>
int main() {
	int a = 5, b = 3;
	int sum = a + b;
	int neg = -a;
	printf("%d %d", sum, neg);
	return 0;
}

Combining Operators in Expressions

Operators of different categories are frequently combined in a single expression, such as mixing arithmetic and relational operators to build a condition used inside an if statement.

Example: Combining Operators in Expressions

c
#include <stdio.h>
int main() {
	int score = 75;
	if (score + 5 > 70) {
		printf("Passed");
	}
	return 0;
}

Operator Precedence Preview

When an expression mixes multiple operators, C evaluates them according to a fixed precedence order -- multiplication and division run before addition and subtraction by default, and parentheses can always override that default order.

Example: Operator Precedence Preview

c
#include <stdio.h>
int main() {
	int result = 2 + 3 * 4;
	printf("%d", result);
	return 0;
}

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