# Rust program to subtract a number without using the '-' operator

Given two numbers, we have to subtract a number without using the '-' operator using Rust program.
Submitted by Nidhi, on September 28, 2021

Problem Solution:

Here, we will read two integer numbers from the user and subtract the second number from the first number without using the "-" operator.

Program/Source Code:

The source code to subtract a number without using the '-' operator is given below. The given program is compiled and executed successfully.

```// Rust program to subtract a number
// without using '-' operator

use std::io;

fn main()
{
let mut n1:i32 = 0;
let mut n2:i32 = 0;
let mut sub:i32 = 0;

let mut input1 = String::new();
let mut input2 = String::new();

println!("Enter number1: ");
n1 = input1.trim().parse().expect("Not a valid number");

println!("Enter number2: ");
n2 = input2.trim().parse().expect("Not a valid number");

sub = n1 + (!n2) + 1;

println!("Subtraction is: {}",sub);
}
```

Output:

```RUN 1:
Enter number1:
10
Enter number2:
20
Subtraction is: -10

RUN 2:
Enter number1:
76
Enter number2:
53
Subtraction is: 23
```

Explanation:

Here, we read the value of n1, n2 from the user. Then we subtracted n2 from n1 using the '!' operator and printed the result.