File 1                                  File 2
1 /* begin routine */                   1 /* find the file extension */
2 void fdiv(                            2 void file_divide(
3    char *fname, // file name          3 char      *fname,
4    char *path)   /* path */           4 char      *path)    // path
5 {                                     5 {
6     int Index1, j;                    6   int i, j; /* begin routine */
7                                       7   while (1)     // loop here
8     while (1)                         8     j = strlen(fname);
9        j = strlen(fname);             9
10    // find the file extension        10   switch (x)
11    if (x == 5) {                     11   {

File 1                                  File 2
1 /* begin routine */                   6    int i, j; /* begin routine */
4     char *path)   /* path */          4  char      *path)    // path
10    // find the file extension        1  /* find the file extension */

Figure 4: Comment Line Matching. (a) Two files; (b) matching comment lines in File 1 and File 2.