determining/sorting variables from lowest to highest

Projects Programming
1

I am building a score keeper for a card game that a group of friends and I play. The program that I have developed has a separate variable for each players score. p1Score, p2Score,etc. At the end of the game I am trying to figure out how to compare up to 10 variables and then sort them from lowest to highest (lowest score wins the game).

int p1Score=100;
int p1rank=0;
int p2Score=150;
int p2rank=0;
int p3Score=155;
int p3rank=0;
int p4Score=75;
int p4rank=0;
int p5Score=80;
int p5rank=0;
int p6Score=100;
int p6rank=0;

so the idea is that the program compares all the scores and then changes the "rank" variables to reflect the lowest to highest ranking. There will also sometimes be ties. I don't know how to phrase the question or accomplish this other than a stampeding herd of "if" statements to get the ranks. Is there a way to do this that I cant see. I saw a way to do it with "sorting a string" but this isnt really a string soooo... Help please.

2

One solution is to use what is called a structure in C. A structure is simply a convenient way to group data. The following program illustrates one way to use a structure:

#define NUMBEROFSCORES 10

struct Score {                     // The structure
  int score;
  int rank;
} myScores[NUMBEROFSCORES];

void setup() {
  int i;
  int val;
  
  randomSeed(analogRead(0));    // Seed random number generator
  Serial.begin(9600);

  for (i = 0; i < NUMBEROFSCORES; i++) {
    myScores[i].score = random(200);         //   Generate random values up to 200
    Serial.print("Score for #");
    Serial.print(i);
    Serial.print(" is: ");
    Serial.println(myScores[i].score);
  }

  Sort();                              // Sort the scores

  Serial.println("After sort: ");
  for (i = 0; i < NUMBEROFSCORES; i++) {
    Serial.print("Score for #");
    Serial.print(i);
    Serial.print(" is: ");
    Serial.println(myScores[i].score);
  }
  
}

void Sort()
{
   int i, j, k, temp;

  for (i = 1; i < NUMBEROFSCORES; i++) {
      for (j = 0; j < NUMBEROFSCORES - 1; j++) {
         if (myScores[j].score > myScores[j + 1].score) {  // Read and swap if necessary
            temp = myScores[j].score;
            myScores[j].score = myScores[j + 1].score;
            myScores[j + 1].score = temp;
         }
      }
  }
}
void loop() {
  // put your main code here, to run repeatedly:

}

There's a bazillion ways to sort data and this is one of the simplest. I'll let you add the code to figure out the rank for each score.

3

Not sure I understand what you are saying but I got the structures as a way of grouping data then examining it/sorting it. Ill have to do some reading to grasp it more. Thanks for the direction tip.

4

In C++ you can use qsort http://www.cplusplus.com/reference/cstdlib/qsort/

Can sort a regular array of ints.

int compare( const void* a, const void* b)
{
     int int_a = * ( (int*) a );
     int int_b = * ( (int*) b );

     if ( int_a == int_b ) return 0;
     else if ( int_a < int_b ) return -1;
     else return 1;
}

qsort( a, 6, sizeof(int), compare )

PS before you get into structures - learn how to use simple arrays first.