find and replace particular string from outside of the file

input:
1.open a .txt file .
2. type something with "hello" word.
3.close the file.
4.copy their file path.
5.paste it in fopen line.
6.replaceable word is "hi"..note: if you change this word .you should alter the for loop condition.
7.run this program with conio.h file function like clrscr();getch(); to the appropriate place.

//find and replace string from outside of the file.
#include"stdio.h"
void main(void)
{
FILE *ft;
char k,ch,replace[3],find[6];
find="hello";
replace="hi";
k=' ';
int i=1,noc=0;
ft=fopen("C:\\KARTHI\\tc\\tmp\\record.txt","r+");
if(ft==NULL)
{
puts("cannot open file\n");
exit(-1);
}else
puts("file is available\n");
while(1)
{
ch=getc(ft);
if(ch==EOF)
break;
else if(ch==find[0])
{
for(i=1;i<=4;i++)
{
if(find[i]!=getc(ft))
{
fseek(ft,-i,SEEK_CUR); goto flag;
}
}
fseek(ft,-(i),SEEK_CUR);
for(i=0;i<=1;i++)
fputc(replace[i],ft);
for(i=2;i<=4;i++) fputc(k,ft);
}
flag:noc++;
}
printf("%s",find);
fclose(ft);
printf("\ntotal number of character%d\n",noc);
}

output: 1.after run this program;
2.open that .txt file. if file exit any "hello" string, then that will replaced as "hi ".
3.Otherwise no change in the contents.