Prog#199 B: occurrence of word

/*
occurence of word
Program#199 B
*/
#include<stdio.h>
main(int argc,char *argv[])
{
int i,j,k,c,l;
char a[81], b[10];
FILE *fp;
if(argc!=2)
{
printf("error. no.of arg");
return 0;
}
fp=fopen (argv[1], "r");
if(fp==NULL)
{
printf("file open error");
return 0;
}
c=0;
for(i=0;(b[i]=getchar())!='$';i++)
b[i]='\0';
for(i=0;(a[i]=getc(fp))!=EOF;i++)
{
if(a[i]=='\n')
{
a[i]='\0';
j=0;
while(a[j]!='\0')
{
k=j;
for(l=0;((b[l]==a[k])&&(b[l]!='\0'));l++)
k++;
if(b[l]=='\0')
c++;
j++;
}
i=-1;
}
}
printf("no. of times: %d", c);
fclose(fp);
}