Reference Card (ANSI)
main with args
function denition
local variable declarations
include library les
include user les
constant & macro denitions
function declarations
external variable declarations
main routine
local variable declarations
ram Structure/Functions
{
e <lename >
e "lename "
name value
(type 1 ,: : : )
me
{
ations
ments
(arg 1 ,: : : )
ations
ments
value ;
n
t argc, char *argv[])
:::
Types/Declarations
r (1 byte)
tants
ngle precision)
uble precision)
6 bit integer)
bit integer)
and negative
itive
to int, float,
tion constant
(unchanging) value
external variable
variable
source le
char
int
float
double
short
long
signed
unsigned
*int, *float,: : :
enum
const
extern
register
static
void
struct
typedef
sizeof
sizeof(
)
typename
object
type name
e
ame by data type
n object (type is size_t)
data type (type is size_t)
L
l
F
f
e
0
0x
0X
a
\
\x \n, \r, \t, \b
\\, \?, \, \"
"abc: : : de"
type name =value
type name []={value 1 ,: : : }
char name []="string "
ooo
hh
or
or
or
x)
x)
tial form
rex zero)
mal (prex zero-ex)
r constant
r constant (octal)
r constant (hexadecimal)
cr, tab, backspace
haracters
nstant (ends with \0)
alization
variable
array
char string
1998 Joseph H. Silverman Permissions on back. v1.0
Operators
:::
arithmetic operations
+, -, *, /
modulus (remainder)
%
comparisons
==, !=, >, >=, <, <=
and, or, not [logical ops]
&&, ||, !
cast expression to type
(type ) expr
increment, decrement
++, -and, or (incl), or (excl) [bit ops]
&, |, ^
left, right shift, ones compl. [bit ops]
<<, >>, ~
assignment operators
+=, -=, *=,
conditional expression
expr 1 ? expr 2 : expr 3
object pointed to by pointer
*pointer
address of object
&name
structure member operator
name .member
structure pointer
pointer ->member
expression evaluation separator
,
Flow of Control
statement terminator
;
block delimeters
{ }
comment delimeters
/* */
exit from switch, while, do, for
break
next iteration of while, do, for
continue
go to
goto label
label
label :
return value from function
return expr
terminate execution
exit(arg )
Flow Constructions (if/while/for/do/switch)
if (expr ) statement
else if (expr ) statement
else statement
while (expr )
statement
for (expr 1 ; expr 2 ; expr 3 )
statement
do
statement
while(expr );
expr
const statement 1 break;
const statement 2 break;
statement
switch (
) {
case
1:
case
2:
default:
}
Pointers & Arrays
pointer
name
type name
name dim ]
name dim 1 ,: : : ]
pointer ->member
*
&
*
[
[
void *
object pointed to by pointer
address of object name
pointer declaration
array
multi-dim array
generic pointer
structure pointer
type *name
type *f()
type (*pf)()
Pointer Declarations
pointer to type
function f returning pointer to type
pointer pf to function returning type
Input/Output
Standard I/O
<
<stdio.h>
:::
:::
:::)
:::)
)
)
standard input stream
stdin
standard output stream
stdout
standard error stream
stderr
end of le
EOF
get a character
getchar()
print a character
putchar(chr )
print formatted data
printf("format ",arg 1 ,
print to string s
sprintf(s,"format ",arg 1 ,
read formatted data
scanf("format ",&name 1 ,
read from string s
sscanf(s,"format ",&name 1 ,
read line to string s ( max chars)
gets(s,max)
print string s
puts(s)
File I/O
c
p
w
<
structure template
declaration of members
w:pc
:::
:::
declare le pointer
FILE *fp
pointer to named le
fopen("name ","mode ")
modes: r (read), w (write), a (append)
get a character
getc(fp )
write a character
putc(chr ,fp )
write to le
fprintf(fp ,"format ",arg 1 ,
)
read from le
fscanf(fp ,"format ",arg 1 ,
)
close le
fclose(fp )
non-zero if error
ferror(fp )
non-zero if EOF
feof(fp )
read line to string s ( max chars)
fgets(s,max,fp )
write string s
fputs(s,fp )
Codes for Formatted I/O: "%-+ 0 "
left justify
+
print with sign
space print space if no sign
0
pad with leading zeros
min eld width
precision
conversion character:
integer
u unsigned
single char
s char string
double
e,E exponential
octal
x,X hexadecimal
pointer
n number of chars written
same as f or e,E depending on exponent
d,i
c
f
o
p
g,G
Structures
tag {
declarations
struct
};
b
b
create structure
struct tag name
member of structure from template
name .member
member of pointed to structure
pointer -> member
Example. (*p).x and p->x are the same
one value, multiple type structure
union
bit eld with bits
member :
lename
lename
name text
name var text
Reference Card (ANSI)
eprocessor
ibrary le
user le
ment text
ment macro
mple.
<errno.h>
<setjmp.h>
<stdlib.h>
<ctype.h>
<float.h>
<signal.h>
<string.h>
<limits.h>
<stdarg.h>
<time.h>
name
name
#include <
>
#include "
"
#define
#define
(
)
#define max(A,B) ((A)>(B) ? (A) : (B))
#undef
#
##
#if, #else, #elif, #endif
#ifdef, #ifndef
defined(
)
\
tring in replace
nate args and rescan
nal execution
dened, not dened?
ned?
inuation char
<ctype.h>
<math.h>
<stdio.h>
I Standard Libraries
.h>
.h>
.h>
acter Class Tests
isalnum(c)
isalpha(c)
iscntrl(c)
isdigit(c)
isgraph(c)
islower(c)
isprint(c)
ispunct(c)
isspace(c)
isupper(c)
isxdigit(c)
tolower(c)
toupper(c)
<string.h>
meric?
ic?
character?
digit?
character (not incl space)?
se letter?
character (incl space)?
char except space, letter, digit?
rmfeed, newline, cr, tab, vtab?
ase letter?
mal digit?
to lower case?
to upper case?
g Operations
e strings, cs,ct are constant strings
fs
strlen(s)
to s
strcpy(s,ct)
to n chars
strncpy(s,ct,n)
nate ct after s
strcat(s,ct)
to n chars
strncat(s,ct,n)
cs to ct
strcmp(cs,ct)
y rst n chars
strncmp(cs,ct,n)
to rst c in cs
strchr(cs,c)
to last c in cs
strrchr(cs,c)
hars from ct to s
memcpy(s,ct,n)
hars from ct to s (may overlap) memmove(s,ct,n)
n chars of cs with ct
memcmp(cs,ct,n)
to rst c in rst n chars of cs memchr(cs,c,n)
to rst n chars of cs
memset(s,c,n)
Standard Utility Functions
<stdlib.h>
absolute value of int n
abs(n)
absolute value of long n
labs(n)
quotient and remainder of ints n,d
div(n,d)
retursn structure with div_t.quot and div_t.rem
quotient and remainder of longs n,d
ldiv(n,d)
returns structure with ldiv_t.quot and ldiv_t.rem
pseudo-random integer [0,RAND_MAX]
rand()
set random seed to n
srand(n)
terminate program execution
exit(status)
pass string s to system for execution
system(s)
atof(s)
atoi(s)
atol(s)
strtod(s,endp)
strtol(s,endp,b)
strtoul(s,endp,b)
Conversions
convert string s to double
convert string s to integer
convert string s to long
convert prex of s to double
convert prex of s (base b) to long
same, but unsigned long
calloc(nobj,size)
malloc(size)
realloc(pts,size)
free(ptr)
Storage Allocation
allocate storage
allocate storage
change size of object
deallocate space
Array Functions
<time.h>
search array for key
bsearch(key,array,n,size,cmp())
sort array ascending order
qsort(array,n,size,cmp())
Time and Date Functions
<stdarg.h>
processor time used by program
clock()
Example. clock()/CLOCKS_PER_SEC is time in seconds
current calendar time
time()
time2 -time1 in seconds (double)
difftime(time2 ,time1 )
arithmetic types representing times
clock_t,time_t
structure type for calendar time comps
tm
tm_sec
seconds after minute
tm_min
minutes after hour
tm_hour
hours since midnight
tm_mday
day of month
tm_mon
months since January
tm_year
years since 1900
tm_wday
days since Sunday
tm_yday
days since January 1
tm_isdst
Daylight Savings Time ag
convert local time to calendar time
mktime(tp)
convert time in tp to string
asctime(tp)
convert calendar time in tp to local time ctime(tp)
convert calendar time to GMT
gmtime(tp)
convert calendar time to local time
localtime(tp)
format date and time info strftime(s,smax,"format ",tp)
tp is a pointer to a structure of type tm
Variable Argument Lists
declaration of pointer to arguments
va_list name ;
initialization of argument pointer va_start(name ,lastarg )
lastarg is last named parameter of the function
access next unamed arg, update pointer va_arg(name ,type )
call before exiting function
va_end(name )
Mathematical Functions
y=x
<math.h>
<limits.h>
arguments and returned values are double
trig functions
sin(x), cos(x), tan(x)
inverse trig functions
asin(x), acos(x), atan(x)
arctan( )
atan2(y,x)
hyperbolic trig functions
sinh(x), cosh(x), tanh(x)
exponentials & logs
exp(x), log(x), log10(x)
exponentials & logs (2 power)
ldexp(x,n), frexp(x,*e)
division & remainder
modf(x,*ip), fmod(x,y)
powers
pow(x,y), sqrt(x)
rounding
ceil(x), floor(x), fabs(x)
8
0
+32767
-32767
+2147483647
-2147483647
+127
-127
+32767
-32767
255
65535
4294967295
65536
<float.h>
bits in char
max value of char
min value of char
max value of int
min value of int
max value of long
min value of long
max value of signed char
min value of signed char
max value of short
min value of short
max value of unsigned char
max value of unsigned int
max value of unsigned long
max value of unsigned short
Integer Type Limits
CHAR_BIT
CHAR_MAX
CHAR_MIN
INT_MAX
INT_MIN
LONG_MAX
LONG_MIN
SCHAR_MAX
SCHAR_MIN
SHRT_MAX
SHRT_MIN
UCHAR_MAX
UINT_MAX
ULONG_MAX
USHRT_MAX
2
6
1E-5
1E+37
1E-37
10
1E-9
1E+37
1E-37
x
x
:
:
x
x
6
6
:
:
radix of exponent rep
oating point rounding mode
decimal digits of precision
smallest so 1 0 + = 1 0
number of digits in mantissa
maximum oating point number
maximum exponent
minimum oating point number
minimum exponent
decimal digits of precision
smallest so 1 0 + = 1 0
number of digits in mantissa
max double oating point number
maximum exponent
min double oating point number
minimum exponent
Float Type Limits
FLT_RADIX
FLT_ROUNDS
FLT_DIG
FLT_EPSILON
FLT_MANT_DIG
FLT_MAX
FLT_MAX_EXP
FLT_MIN
FLT_MIN_EXP
DBL_DIG
DBL_EPSILON
DBL_MANT_DIG
DBL_MAX
DBL_MAX_EXP
DBL_MIN
DBL_MIN_EXP
c 1998 Joseph H. Silverman
July 1998 v1.0. Copyright Permission is granted to make and distribute copies of this card provided the copyright notice and this permission notice are preserved on
all copies.
Send comments and corrections to J.H. Silverman, Math. Dept., Brown
Univ., Providence, RI 02912 USA. hjhs@math.brown.edui