Lexical Analysis C language

#include <stdio.h> #include <string.h>char prog[80],token[8],ch;int syn,p,m,n,sum;char *keyword[6]={" Begin "," if "," then "," while "," does "," End "};void getsym (); main () {p=0; printf (" Please input a string (end With ' # '): ");    do{scanf ("%c", &ch);    Prog[p++]=ch; }while (ch!= ' # '); P=0;    do{Getsym ();          Switch (SYN) {case 11:printf ("(%-10d%5d) \ n", Sum,syn);      Break          case-1:printf ("You have input a wrong string\n");          Getch ();      Exit (0);          Default:printf ("(%-10s%5d) \ n", Token,syn);      Break    }}while (syn!=0); Getch ();    }void getsym ()//lexical analysis function {sum=0;    for (m=0;m<8;m++) token[m++]=null;    Ch=prog[p++];    m=0; while (ch== ") | | (ch== ' \ n '))    Ch=prog[p++]; if ((ch<= ' z ') && (ch>= ' a ')) | |      ((ch<= ' Z ') && (ch>= ' A '))) {while ((ch<= ' z ') && (ch>= ' a ')) | | ((ch<= ' Z ') && (ch>= ' A ')) | |      (ch>= ' 0 ') && (ch<= ' 9 ')))       {token[m++]=ch;      Ch=prog[p++]; } p-;      syn=10;         for (n=0;n<6;n++) if (strcmp (token,keyword[n)) ==0) {syn=n+1;       Break }} else if ((ch>= ' 0 ') && (ch<= ' 9 ')) {while ((ch>= ' 0 ') && (ch<= ' 9 ')) {Sum=sum*10+c      H ' 0 ';    Ch=prog[p++];    } p--;      syn=11;          } else switch (CH) {case ' < ': token[m++]=ch;           Ch=prog[p++];               if (ch== ' = ') {syn=22;            Token[m++]=ch;               } else {syn=20;            p--;     } break;          Case ' > ': token[m++]=ch;          Ch=prog[p++];              if (ch== ' = ') {syn=24;            Token[m++]=ch;              } else {syn=23;            p--;     } break;          Case ' + ': token[m++]=ch;          Ch=prog[p++];              if (ch== ' + ') {syn=17;            Token[m++]=ch;              } else {syn=13;            p--;     } break; Case '-': token[m++]=ch;          Ch=prog[p++];              if (ch== '-') {syn=29;            Token[m++]=ch;              } else {syn=14;            p--;     } break;          Case '! ': ch=prog[p++];             if (ch== ' = ') {syn=21;           Token[m++]=ch;             } else {syn=31;          p--;     } break;          Case ' = ': token[m++]=ch;          Ch=prog[p++];              if (ch== ' = ') {syn=25;            Token[m++]=ch;              } else {syn=18;            p--;     } break;           Case ' * ': syn=15;           Token[m++]=ch;     Break           Case '/': syn=16;           Token[m++]=ch;     Break           Case ' (': syn=27;           Token[m++]=ch;     Break           Case ') ': syn=28;           Token[m++]=ch;     Break           Case ' {': syn=5;           Token[m++]=ch;     Break           Case '} ': syn=6;           Token[m++]=ch;     Break        Case '; ': syn=26;  Token[m++]=ch;     Break           Case ' \ ': syn=30;           Token[m++]=ch;     Break           Case ' # ': syn=0;           Token[m++]=ch;     Break           Case ': ': syn=17;           Token[m++]=ch;    Break         Default:syn=-1;       Break    } token[m++]= ' + '; }

Lexical Analysis C language