Zig Arithmetic

Arithmetic is doing maths with numbers using operators like + and -.

Addition and subtraction give new numbers

The + operator adds. The - operator subtracts.

const std = @import("std");

pub fn main() !void {
    const out = std.io.getStdOut().writer();
    const a = 14;
    const b = 5;
    try out.print("{d}\n", .{a + b});
    try out.print("{d}\n", .{a - b});
}

Multiplication and division give new numbers

The * operator multiplies. The / operator divides.

const std = @import("std");

pub fn main() !void {
    const out = std.io.getStdOut().writer();
    const a = 7;
    const b = 6;
    try out.print("{d}\n", .{a * b});
    try out.print("{d}\n", .{24 / 4});
}

Remainder and brackets change the result

The % operator shows the leftover. Brackets run before the rest.

const std = @import("std");

pub fn main() !void {
    const out = std.io.getStdOut().writer();
    try out.print("{d}\n", .{17 % 5});
    try out.print("{d}\n", .{(3 + 4) * 2});
}

Example

const std = @import("std");

pub fn main() !void {
    const out = std.io.getStdOut().writer();
    const unit_price = 8;
    const count = 3;
    const fee = 2;
    const paid = 30;
    const subtotal = unit_price * count;
    const total = subtotal + fee;
    const change = paid - total;
    try out.print("{d}\n", .{subtotal});
    try out.print("{d}\n", .{total});
    try out.print("{d}\n", .{change});
}

Key points

Addition: the + operator adds two numbers together.
Subtraction: the - operator takes the second number away from the first.
Multiplication: the * operator multiplies two numbers.
Division: the / operator divides the first number by the second.
Remainder: the % operator gives what is left over after division.
Parentheses: round brackets group operations that must run first.

In this example, the subtotal multiplies the unit price 8 by the count 3 to get 24. The total adds the fee 2 to get 26. The change subtracts 26 from the 30 paid and prints 4.

Note

Zig does not mix an integer and a float in one operation, so both sides must share a type.

Try it Yourself

Edit the code, then press Run.

Running is simulated

const std = @import("std");

pub fn main() !void {
    const out = std.io.getStdOut().writer();
    const unit_price = 8;
    const count = 3;
    const fee = 2;
    const paid = 30;
    const subtotal = unit_price * count;
    const total = subtotal + fee;
    const change = paid - total;
    try out.print("{d}\n", .{subtotal});
    try out.print("{d}\n", .{total});
    try out.print("{d}\n", .{change});
}

Exercise

What does (2 + 3) * 4 give?

14 20 24 9