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 # include & lt; stdio.h> 
# include & lt; Ctype. H> 
# include & lt; string.h> 

Char token_buf [128]. 
Int state; 
Int start; 
Char cbuf [128]. 
Int forward=1; 
Void back () {
The forward -; 
} 
Void next () {
Forward + +; 
} 
Char * gettoken () {
Int I, j=0; 
For (I=start; i <=forward; I + +) {
Token_buf [j++]=cbuf [I]; 
} 
Token_buf [j]='\ 0'; 
Return token_buf; 
} 
Char nextchar () {
Forward + +; 
Return cbuf (forward); 
} 
Char * nexttoken () {
char c; 
State=12; 
While (1) {
The switch (state) {
Case 12: 
C=nextchar (); 
If (c=='-' | | c=='+') 
Start=forward; 
Else if (isdigit (c)) {
If (start==1) start=forward; 
State=13; 
} else {
Start=1; 
The next (); 
} 
break; 
Case 13: 
C=nextchar (); 
If (isdigit (c)) 
State=13; 
Else if (c=='e' | | c=='e') 
State=16; 
Else if (c==') 
State=14; 
The else 
State=19; 
break; 
Case 14: 
C=nextchar (); 
If (isdigit (c)) 
State=15; 
break; 
Case 15: 
C=nextchar (); 
If (isdigit (c)) 
State=15; 
Else if (c=='e' | | c=='e') 
State=16; 
The else 
State=19; 
break; 
Case 16: 
C=nextchar (); 
If (isdigit (c)) 
State=18; 
Else if (c=='+' | | c=='-') 
State=17; 
break; 
Case 17: 
C=nextchar (); 
If (isdigit (c)) 
State=18; 
break; 
Case 18: 
C=nextchar (); 
If (isdigit (c)) 
State=18; 
The else 
State=19; 
break; 
Case 19: 
The back (); 
Return gettoken (); 
} 
} 
} 
Int main () {
The fgets (cbuf, 128, stdin); 
If (=='\ n' cbuf [strlen (cbuf) - 1)) cbuf [strlen (cbuf) - 1)=0. 
While (1) {
Start=1; 
Printf (" % s \ n ", the nexttoken ()); 
If (forward & gt;=(int) strlen (cbuf) - 1) {
return 0; 
} 
} 
} 
//input: 12.3 * * * * * * * * * klj12.2 e2jj778 
//output: 
//12.3 
//12.2 e2 
//778 
//

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