# include & ltstdlib.h & gt
int main(void)
{
char ch，filename[ 128]，str[2 1]，line[20 1]；
int i = 0，j，k，m，lineNum = 0，isfirst = 0，firstLine = - 1，last line =- 1；
FILE * fp
Printf ("Enter file name and string:");
Scanf("%s%s ",file name, string);
Printf("-file content:-\ n ");
Fp = fopen (file name, "r");
if (fp == NULL)
{
Printf ("Cannot open file! \ n ")；
Exit (1);
}
And (! feof(fp))
{
ch = fgetc(FP)；
line[I]= ch；
i++；
If (ch == '\n')// If a line break is encountered,
{
linenum++； //Cumulative line
putchar(ch)； //Output newline character
line[I]= ' \ 0 '； //Set the string end of the line.
I = 0； //I clear
}
Else if (ch == EOF)// If the end of the file is reached,
{
linenum++； //Cumulative line
line[I]= ' \ 0 '； //Set the string end of the line.
}
Else// The rest of the characters are directly output to the screen.
{
putchar(ch)；
}
//Complete the output;
If (ch == '\n' || ch == EOF)// End of line or file encountered.
{
for (j = 0，k = 0； Ok [j]! = '\0'; j++)
{
//Check whether the string of line line contains the input string str (case-insensitive).
if((line[j]= = str[k])| |(line[j]= =(str[k]-32))| |(line[j]= =(str[k]+32)))
{
for(m = j； ((line[m]= = str[k])| |(line[m]= =(str[k]-32))| |(line[m]= =(str[k]+32)))
& amp& ampstr[k]！ = '\0'; k++，m++)
{
;
}
if (str[k] == '\0 ')
{
if (isfirst == 0)
{
FirstLine = lineNum// Calculates the first equal occurrence of the line.
is first = 1；
}
LastLine = lineNum// Calculates the line where the last equation is located.
}
else if (line[m]！ = str[k])
{
k = 0；
}
}
}
}
}
putchar(' \ n ')；
Printf("-file summary:-\ n ");
Printf("%d line, first line: %d, last line: %d\n ",lineNum, first line, last line);
Returns 0;
}