howtothings.co.uk

Code for the ELU Rating system, explained here: http://mcompute.co.uk/showthread.php?tid...63#pid6363
Code requires math.h to be imported for the pow() and round() functions.

Updated for a who's won picker. Also for those wondering (Pack3t) I've done some thinking, and there is a technical limit. When it gets to a point where the percentage chance of the other is > 0.5% (Due to the round function, so really 0%) then nothing changes.
This program also allows for you to enter a long string, E.G I could enter 111 to signify Pack3t won 3 times or 2222 to signify Sharn won 4 times.
[code=c]
#include <stdio.h>
#include <math.h>
#include <stdlib.h>

#define maxcandidates 20
#define maxlength 15
#define CONFIGURATION "configuration.txt"

int elupercentage( int Ra, int Rb );
void eluNewBR( int *winner, int *loser, int winpercent, int losepercent );
int scanfile();
void savefile(int savelimit);

int baserating[maxcandidates];
char candidate[maxcandidates][maxlength];

main(){
int percent1, percent2;
int limit = scanfile();
int x, y;
char c;
int badchar = 0;

do{
if(!badchar){
x = rand() % limit;
y = rand() % limit;
while ( x == y )
y = rand() % limit;
printf("\n > For %s to win enter 1\n", candidate[x]);
printf(" > For %s to win enter 2\n", candidate[y]);
printf(" > Hit 3 to save and exit\n\n");

percent1 = elupercentage( baserating[x], baserating[y] );
percent2 = elupercentage( baserating[y], baserating[x] );
printf("Base Rating of %s: %d\n", candidate[x], baserating[x]);
printf("Base Rating of %s: %d\n", candidate[y], baserating[y]);
printf("Chance of %s winning: %d%% \n", candidate[x], percent1);
printf("Chance of %s winning: %d%% \n", candidate[y], percent2);
}

badchar = 0;
c = getchar();
if (c == '1')
eluNewBR( &baserating[x], &baserating[y], percent1, percent2 );
else if (c == '2')
eluNewBR( &baserating[y], &baserating[x], percent1, percent2 );
else if (c == '3')
savefile(limit-1);
else
badchar = 1;
}while(1);

}

int elupercentage( int Ra, int Rb ){
return round(100 / ( 1+pow(10, (((float)Rb - (float) Ra) / 400))));
}

void eluNewBR( int *winner, int *loser, int winpercent, int losepercent ){
*winner += 100 - winpercent;
*loser -= losepercent;
}

int scanfile(){
FILE *config = fopen(CONFIGURATION, "r");
int z, y, i, x = 0;
char buffer[5]; //Allows for BR up to 99999
int username = 1;
if (config == NULL){
printf("Error!\n");
exit(1);
}

for(i = 0;; i++){
z = fgetc(config);
if (z == '\n' || z == EOF){
if (username == 1)
username = 0;
else if (username == 0){
baserating[x] = atoi(buffer);
x++;
for( y = 0; y <= 5; y++)
buffer[y] = 0;
username = 1;
}
i = -1;
if ( z == EOF )
break;
} else {
if (username == 1){
candidate[x][i] = z;
} else if(username == 0){
buffer[i] = z;
}
}

}
fclose(config);
return x;
}

void savefile(int savelimit){
FILE *config = fopen(CONFIGURATION, "w");
int length, place, position = 0;
char buffer[5]; //Matching previous buffer.


for ( place = 0; place <= savelimit; position = 0, place++){
while ( candidate[place][position] != '\0' ){
fputc( candidate[place][position], config );
position++;
}
fputc('\n', config);


length = sprintf ( buffer, "%d", baserating[place] );
for ( position = 0; position <= length; position++ )
fputc(buffer[position], config);

fputc('\n', config);

}
fclose(config);
exit(1);
} [/code]

Updated the code so it doesn't produce warnings when compiling. I did this by changing \% for %% in the printf statements.

UPDATE: Changed my example of how the code can be used so that it allows you to pick a winner, see first post.

UPDATE: Added a configuration.txt option, It MUST be formatted like so:
Username
Baserating
Username
Baserating

Etc. etc.

Mark
10000000000000

I haven't got my same file with me, But if I remember correctly it's something like:
Pack3t
700
Sharn
500
Latch
600
Mark
250
Drumm
100

Wait.. Does that mean Sharn is more likely to get rated over myself and you?

It would appear that is the case.....but yet not over me.
As a side note it would seem someone quietly took a lot of suggestions from an old fart, good times.

You were my guidance on this Pack3t :tongue. When you ain't 100% confident in what you're doing, it's good to have someone that can say "Yeah, that will work"