Using arrays as parameters and return values

functionTest.ino

/**************************************************************  
  25, Jun., 2017
  Copyright by Jarvus Chen. All Rights Reserved.
  www.jarvus.net
************************************************************** */

void setup() {
  Serial.begin(9600);
  Serial.println("Start");
}

void loop() {

//  Case A: multiple input value / sigle output value
  int ansA = caseA(1, 2);
  Serial.println("For Case A:");
  Serial.println(ansA);
  
//  Case B: multiple input value / multiple output value ( single output array )
  int* ansB = new int[2];
  ansB = caseB(1, 2);
  Serial.println("For Case B:");
  Serial.println(ansB[0]);
  Serial.println(ansB[1]);
  delete ansB;
  
//  Case C: single input array / single output array
  int dataC[2] = {1, 2};
  int* ansC = new int[2];
  ansC = caseC(&dataC[0]);
  Serial.println("For Case C:");
  Serial.println(ansC[0]);
  Serial.println(ansC[1]);
  delete ansC;

//  Case D: multiple input 2D array / multiple output 2D array
  int dataD1[2][2] = { {1, 2},{3, 4} };
  int dataD2[2][2] = { {4, 3},{2, 1} };
  
  int ansD1[2][2] = { {0, 0},{0, 0} };
  int ansD2[2][2] = { {0, 0},{0, 0} };
  
  caseD(&dataD1[0], &dataD2[0], &ansD1[0], &ansD2[0]);
  Serial.println("For Case D:");
  Serial.print(ansD1[0][0]);
  Serial.println(ansD1[0][1]);
  Serial.print(ansD1[1][0]);
  Serial.println(ansD1[1][1]);
  
  Serial.print(ansD2[0][0]);
  Serial.println(ansD2[0][1]);
  Serial.print(ansD2[1][0]);
  Serial.println(ansD2[1][1]);
  
  delay(5000);
}

//  Case A: multiple input value / sigle output value
int caseA(int a, int b){
  return a+b;
}

//  Case B: multiple input value / multiple output value ( single output array )
int* caseB(int a, int b){
  int* ans = new int[2];
  ans[0] = a+b;
  ans[1] = a-b;
  return ans;
}

//  Case C: single input array / single output array
int* caseC(int a[]){
  int* ans = new int[2];
  ans[0] = a[0]+a[1];
  ans[1] = a[0]-a[1];
  return ans;
}

//  Case D: multiple input 2D array / multiple output 2D array
void caseD(int a[][2], int b[][2], int ans1[][2], int ans2[][2]){
  ans1[0][0] = a[0][0]+b[0][0];
  ans1[0][1] = a[0][1]+b[0][1];
  ans1[1][0] = a[1][0]+b[1][0];
  ans1[1][1] = a[1][1]+b[1][1];

  ans2[0][0] = a[0][0]*b[0][0];
  ans2[0][1] = a[0][1]*b[0][1];
  ans2[1][0] = a[1][0]*b[1][0];
  ans2[1][1] = a[1][1]*b[1][1];
}