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Arithmetic Expression

Description

Consider an arithmetic expression of the form a#b=c. Check whether it is possible to replace # with one of the four signs: +, -, * or / to obtain a correct expression.

Example

  • For a = 2, b = 3, and c = 5, the output should be arithmeticExpression(a, b, c) = true.

We can replace # with a + to obtain 2 + 3 = 5, so the answer is true.

  • For a = 8, b = 2, and c = 4, the output should be arithmeticExpression(a, b, c) = true.

We can replace # with a / to obtain 8 / 2 = 4, so the answer is true.

  • For a = 8, b = 3, and c = 2, the output should be arithmeticExpression(a, b, c) = false.
    • 8 + 3 = 11 ≠ 2;
    • 8 - 3 = 5 ≠ 2;
    • 8 * 3 = 24 ≠ 2;
    • 8 / 3 = 2.(6) ≠ 2.

    So the answer is false.

Input/Output

  • [execution time limit] 4 seconds (js)

  • [input] integer a

    Guaranteed constraints:
    1 \leq a \leq 20.

  • [input] integer b

    Guaranteed constraints:
    1 \leq b \leq 20.

  • [input] integer c

    Guaranteed constraints:
    0 \leq c \leq 20.

  • [output] boolean

    • true if the desired replacement is possible, false otherwise.

[JavaScript (ES6)] Syntax Tips

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// Prints help message to the console
// Returns a string
function helloWorld(name) {
    console.log("This prints to the console when you Run Tests");
    return "Hello, " + name;
}

Solution

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function arithmeticExpression(a, b, c) {
	var ops = [
		(d, e) => d + e,
		(d, e) => d - e,
		(d, e) => d * e,
		(d, e) => d / e
	];
	return ops.some(f => f(a, b) === c);
}