2 Player Rock Paper Scissors Game

Hello I am doing my best to create see title but I am not sure what is wrong with my program.

So basically 2 players enter there names and it is stored in a string and one player takes a turn selecting rock paper or scissors.

The program will then return a printf message indicating which player won. Here is the code so far.

Code:

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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*coded by Roman R*/


    char P1_Name[20], P2_Name[20];
    char rock, paper, scissors;
    char P1Choice, P2Choice, Greaterchoice;
   
    if ((P1Choice==rock && P2Choice==scissors) || (P1Choice==scissors && P2Choice==paper) || (P1Choice==rock && P2Choice==scissors)|| (P1Choice==paper && P2Choice==rock) || (P1Choice==scissors && P2Choice==paper) || (P1Choice==rock && P2Choice==scissors)) {
          Greaterchoice = 0;
         
    else if ((P1Choice==rock && P2Choice==paper) || (P1Choice==paper &&P2Choice==scissors) || (P1Choice==scissors && P2Choice==rock)); {
            Greaterchoice = 1;
    else {
            Greaterchoice = 3;
       
        return Greaterchoice;
   
    printf("Player1 Enter your name.:")     
            scanf ("%s", P1_Name);
    printf("Player2 Enter your name.:");
            scanf ("%s", P2_Name);
    printf("%s%s, Enter rock paper or scissors:\n", P1_Name, P2_Name);
            scanf("%c%c", &P1Choice, &P2Choice);
        return Greaterchoice;
             
int main() {
      if Greaterchoice = 0
        printf("%s", Won, P1_Name);
        else if Greaterchoice = 1
        printf("%s", won, P2_Name)
        else
        printf("It,s a draw");
    return 0;
}

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