You don’t return any value, e.g. this is the last method.

don't return java

EXAMPLE

modifier + void + methodName + () + { + }

the start method doesn't return anything only gives output to the user 
int difficultSum1() {
	int q = 30;
	int r = 10;
	int a = 10 + 30*q;
	int z = q * q + a;
	return a * q + q;
}

int difficultSum2 () {
	int m = 20;
	int s = 30 + 60 * m;
	int l = s + s * m;
	return m * s * l;
}

void start() {
	int result = difficultSum1() + difficultSum2();
	System.out.println("This is the result: " + result);
}