How do I using a function to build a matrix?

#include<stdio.h>         
/*I am a fish of C，I am writing a dynamic programming matrix for DNA alignment.  */
#define p -0.005        /* the program is quite easy,just create a array first */
float f(int,int);
int main()
{
    float table[6][6];   /*then fill the array with some fixed number*/
    int x,y,i;
    table[0][0]=p;   
    for(i=1;i<=5;i++)
    table[i][0]=i*p;
    for(i=1;i<=5;i++)
    table[0][i]=i*p;
    for(x=1;x<=5;x++)       /* then fill the array,just using some comparings*/
        for(y=1;y<=5;y++)
        {
            float a,b,c;
            a=table[x-1][y-1]+f( x-1,y-1);
            b=table[x][y-1]+p;
            c=table[x-1][y]+p;
            if(a>=b&&a>=c) table[x][y]=a; 
            if(b>=a&&b>=c) table[x][y]=b;
            if(c>=b&&c>=a) table[x][y]=c;
        }

        for(x=0;x<=5;x++)              /*finally print the number out*/
            for(y=0;y<=5;y++)
            {
                printf("%.6f\t",table[x][y]);
                if (y==5) printf("\n");
            }

    return 0;
}

float f(int x,int y)
{
    char seq1[6],seq2[6];
    float r;
    seq1[6]="ACGTT"; 
    seq2[6]="GCATG";

    if (seq1[x]=='A'&&seq2[y]=='A'||seq1[x]=='T'&&seq2[y]=='T') 
        r=0.99; 
    if (seq1[x]=='G'&&seq2[y]=='G'||seq1[x]=='C'&&seq2[y]=='C')
        r=0.99;
    if(seq1[x]=='A'&&seq2[y]=='T'||seq1[x]=='T'&&seq2[y]=='A')
        r=0.002;
    if(seq1[x]=='A'&&seq2[y]=='G'||seq1[x]=='G'&&seq2[y]=='A')
        r=0.006;
    if(seq1[x]=='A'&&seq2[y]=='C'||seq1[x]=='C'&&seq2[y]=='A')
        r=0.002;
    if(seq1[x]=='T'&&seq2[y]=='G'||seq1[x]=='G'&&seq2[y]=='T')
        r=0.002;
    if(seq1[x]=='T'&&seq2[y]=='C'||seq1[x]=='C'&&seq2[y]=='T')
        r=0.002;
    if(seq1[x]=='G'&&seq2[y]=='C'||seq1[x]=='C'&&seq2[y]=='G')
        r=0.006;

    return(r);
}