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Boot> boot rp1

70Boot from xp(0,1,0) at 0176700
Press <CR> to boot, or any other key to abort: 0
: xp(0,1,0)unix
Boot: bootdev=05010 bootcsr=0176700

2.11 BSD UNIX #1: Oct 31 09:13:53 CST 1981  
    root@Sat:/usr/src/sys/VIXEN

attaching sl
attaching lo0

phys mem  = 3915776
avail mem = 3489088
user mem  = 307200

October 31 09:26:16 init: configure system

lp 0 csr 177514 vector 200 attached
rk 0 csr 177400 vector 220 attached
rl 0 csr 174400 vector 160 attached
tm 0 csr 172520 vector 224 attached
xp 0 csr 176700 vector 254 attached
cn 1 csr 176500 vector 310 attached
cn 2 csr 176510 vector 320 attached
Automatic reboot in progress...
Sat Oct 31 09:26:21 CST 1981
Sat Oct 31 09:26:21 CST 1981
checking quotas: done.
Assuming NETWORKING system ...
ifconfig: ioctl (SIOCGIFFLAGS): no such interface
vixen.skn.noip.me: bad value
add net default: gateway 127.0.0.1
starting system logger
checking for core dump... 
preserving editor files
clearing /tmp
standard daemons: update cron accounting.
starting network daemons: inetd rwhod printer.
Sat Oct 31 09:26:22 CST 1981
Oct 31 09:26:22 vixen October 31 09:26:22 init: kernel security level changed from 0 to 1


2.11 BSD UNIX (vixen.skn.noip.me) (console)

login: root
erase, kill ^U, intr ^C
# pwd
/
# ls
.cshrc      .tiprc      disklabel   lost+found  size.c      var
.hushlogin  README      etc         mdec        sys         vmunix
.kermrc     VERSION     generic     mnt         tmp
.login      bin         hanoi.c     netnix      toyset
.mailrc     boot        hello.c     pi.c        unix
.profile    dev         lib         sbin        usr
# more size.c
#include <stdio.h>

main(argc, argv)
    int argc;
    char * argv[];
{
    printf("Size of char: %d byte\n",sizeof(char));
    printf("Size of int: %d bytes\n",sizeof(int));
    printf("Size of long: %d bytes\n",sizeof(long));
    printf("Size of float: %d bytes\n",sizeof(float));
    printf("Size of double: %d bytes\n",sizeof(double));
}
# cc size.c
# ./a.out
Size of char: 1 byte
Size of int: 2 bytes
Size of long: 4 bytes
Size of float: 4 bytes
Size of double: 8 bytes
# 

#include <stdio.h>

#define IN_CODE 1
#define IN_POSSIBLE_COMMENT 2
#define IN_COMMENT 3
#define IN_POSSIBLE_END_OF_COMMENT 4
#define IN_END_OF_COMMENT 5
#define IN_STRING 6
#define IN_CHAR 7

int main()
{
    int state = IN_CODE;
    int c;
    
    while((c=getchar()) != EOF) {
	if (state == IN_END_OF_COMMENT)
	    state = IN_CODE;
	
	if (c == '"' || c == '/' || c == '*' || c == '\'') {
	    if (c == '"' && state == IN_CODE)
		state = IN_STRING;
	    else if (c == '"' && state == IN_STRING)
		state = IN_CODE;
	    else if (c == '/' && state == IN_CODE)
		state = IN_POSSIBLE_COMMENT;
	    else if (c == '/' && state == IN_POSSIBLE_COMMENT)
		putchar('/');
	    else if (c == '*' && state == IN_POSSIBLE_COMMENT)
		state = IN_COMMENT;
	    else if (c != '*' && state == IN_POSSIBLE_COMMENT) {
		putchar('/');
		state = IN_CODE;
	    }
	    else if (c == '*' && (state == IN_COMMENT || state == IN_POSSIBLE_END_OF_COMMENT))
		state = IN_POSSIBLE_END_OF_COMMENT;
	    else if (c == '/' && state == IN_POSSIBLE_END_OF_COMMENT)
		state = IN_END_OF_COMMENT;
	    else if (c != '/' && state == IN_POSSIBLE_END_OF_COMMENT)
		state = IN_COMMENT;
	    else if (c == '\'' && state == IN_CODE)
		state = IN_CHAR;
	    else if (c == '\'' && state == IN_CHAR)
		state = IN_CODE;
	}
	

	if (state == IN_CODE || state == IN_STRING || state == IN_CHAR){
	    putchar(c);
	}
	
	
    }

    return 0;
}

#include <stdio.h>

#define ERROR 1
#define OK 0

#define IN_CODE 1
#define POSSIBLE 2
#define IN_COMMENT 4
#define END 8
#define IN_STRING 16
#define IN_CHAR 32
#define IN_ESCAPE_SEQUENCE 64
#define START 128

int check_input();
int get_new_state(int state, int c);
void count_symbol(int c);
int get_result();
int check_even(int num);
    
int quotes = 0;
int double_quotes = 0;
int open_braces = 0;
int close_braces = 0;
int open_round_brackets = 0;
int close_round_brackets = 0;

    
int main() 
{
    if (check_input() == ERROR) {
	printf("Error found\n");
	return ERROR;
    }
    else {
	printf("Syntax ok\n");
	return OK;
    }
}

int check_input() 
{
    int state, i, c;

    state = IN_CODE;
    while((c = getchar()) != EOF) {
	state = get_new_state(state, c);
	if (state == IN_CODE ||
	    state == IN_COMMENT + POSSIBLE||
	    state == IN_CHAR + START ||
	    state == IN_STRING + START ||
	    state == IN_CHAR + END ||
	    state == IN_STRING + END) {
	    count_symbol(c);
	}
    }
    
    return get_result();
}


void count_symbol(int c) 
{
    if (c == '\'')
	++quotes;
    else if (c == '\"')
	++double_quotes;
    else if (c == '{')
	++open_braces;
    else if (c == '}')
	++close_braces;
    else if (c == '(')
	++open_round_brackets;
    else if (c == ')')
	++close_round_brackets;
}

int get_new_state(int state, int c) 
{
    if (state == IN_COMMENT + END ||
	state == IN_STRING + END ||
	state == IN_CHAR + END)
	state = IN_CODE;
    else if (state == IN_STRING + START)
	state = IN_STRING;
    else if (state == IN_CHAR + START)
	state = IN_CHAR;
    else if (state == IN_CHAR + IN_ESCAPE_SEQUENCE ||
	     state == IN_STRING + IN_ESCAPE_SEQUENCE)
	state = state - IN_ESCAPE_SEQUENCE;
    else if (state == IN_CHAR + IN_ESCAPE_SEQUENCE + END ||
	     state == IN_STRING + IN_ESCAPE_SEQUENCE + END)
	state = state - IN_ESCAPE_SEQUENCE - END;

    if (c == '"' && state == IN_CODE)
	state = IN_STRING + START;
    else if (c == '"' && state == IN_STRING)
	state = IN_STRING + END;
    else if (c == '/' && state == IN_CODE)
	state = IN_COMMENT + POSSIBLE;
    else if (c == '*' && state == IN_COMMENT + POSSIBLE)
	state = IN_COMMENT;
    else if (c != '*' && state == IN_COMMENT + POSSIBLE) 
	state = IN_CODE;
    else if (c == '*' && (state == IN_COMMENT || state == IN_COMMENT + END + POSSIBLE))
	state = IN_COMMENT + END + POSSIBLE;
    else if (c == '/' && state == IN_COMMENT + END + POSSIBLE)
	state = IN_COMMENT + END;
    else if (c != '/' && state == IN_COMMENT + END + POSSIBLE)
	state = IN_COMMENT;
    else if (c == '\'' && state == IN_CODE)
	state = IN_CHAR + START;
    else if (c == '\'' && state == IN_CHAR)
	state = IN_CHAR + END;
    else if (c == '\\' && (state == IN_CHAR || state == IN_STRING))
	state = state + IN_ESCAPE_SEQUENCE + START;
    else if (state == IN_CHAR + IN_ESCAPE_SEQUENCE + START ||
	     state == IN_STRING + IN_ESCAPE_SEQUENCE + START)
	state = state - START + END;
	  

    return state;    
}

int get_result() 
{
    /* printf("quotes: %d\ndouble_quotes: %d\nopen_braces: %d\nclose_braces: %d\nopen_round_brackets: %d\nclose_round_brackets: %d\n", */
    /* 	   quotes, double_quotes, open_braces, close_braces, open_round_brackets, close_round_brackets); */

    if (check_even(quotes) == OK &&
	check_even(double_quotes) == OK &&
	open_braces == close_braces &&
	open_round_brackets == close_round_brackets)
	return OK;
    else
	return ERROR;
}

int check_even(int num)
{
    int m;
    m = num / 2;
    if (m * 2 == num)
	return OK;
    else
	return ERROR;
}