Variable resetting in "if" statement - tried global and static definitions


I’m new to Arduino (and C) programming and sure I’m making a basic error, but I’m stuck. I have 2 momentary switches - whichever one was pushed last should change the RED/GREEN LED output (in this cut down example). It reads the buttons correctly (using the onboard LED as a test) but when I try to use a variable to remember the ‘state’ set by the last button pressed the variable is reset to “1” every loop. I have defined the variable as global and also as a static variable (I think) but it makes no difference.

Any suggestions?

Many thanks


const int P2_Red_LED = 2;          
const int P2_Green_LED = 3;       
const int ledPin = 13;            
const int Give_to_Red = 15;        // (A1)
const int Return_to_Green = 16;    // (A2) 

int Give_to_Red_State;         
int Return_to_Green_State; 

static int P2_Control = 0;            

void setup() 
  pinMode(Give_to_Red, INPUT_PULLUP);
  pinMode(Return_to_Green, INPUT_PULLUP);
  pinMode(P2_Red_LED, OUTPUT);
  pinMode(P2_Green_LED, OUTPUT);
  pinMode(ledPin, OUTPUT);

  digitalWrite(P2_Red_LED, LOW); 
  digitalWrite(P2_Green_LED, HIGH);

  digitalWrite(ledPin, LOW);

void loop() 
  Give_to_Red_State = digitalRead(Give_to_Red);
  Return_to_Green_State = digitalRead(Return_to_Green);
  if ( Return_to_Green_State == LOW )
  P2_Control = 0;
  digitalWrite(ledPin, LOW); // works correctly
  if ( Give_to_Red_State == LOW )
  P2_Control = 1;
  digitalWrite(ledPin, HIGH);   // works correctly

  //  P2_Control = 0 at this point when "Return_to_Green_State" is LOW
  if (P2_Control = 1 )   // code enters the first part of the if statement even when 
                         // P2_Control = 0 as noted above        

  digitalWrite(P2_Red_LED, HIGH);      
  digitalWrite(P2_Green_LED, LOW);      
  digitalWrite(P2_Red_LED, LOW);  
  digitalWrite(P2_Green_LED, HIGH);  
  if (P2_Control = 1 )

Bzzzt. That is not the comparison operator.

Doh! Years of programming in other languages (and a few years ago!) - habits are hard to break but many thanks. I'll try not to make that mistake again!!