, if , :
:
if ( ) {
.
}
:
if ( ) {
.
}
else {
.
}
-----------------------------------------------------------------------------------------
. .
K&R ( ): 8 ( ) , 4 .
if (<cond>) {<body>}
( Microsoft Visual Studio): , , ; , ( ) , ; , ; , ( ).
if (<cond>){<body>}( ): 8 .
if (<cond>){<body>}GNU ( GNU): 2 , .
if (<cond>){<body>}-----------------------------------------------------------------------------------------
:
1? 2: 3
1 : , , , , . 1 0 ( true), 2 . 1 0 ( false), 3, .
(a > b)? a = 1: b = 2;
cout << ((a > b)? a = 1: b = 2) << endl;
d = (c >= 0)? c: -c;
max = a <= b? b: a; // max b
- .
, :
if ('A' <= c && c <= 'Z')
printf("%c\n", 'a'+c-'A');
|
|
else
printf("%c"\n, c); //6116 +( -4116)
:
printf("%c", ('A' <= c && c <= 'Z')? ('a'+c -'A'): c);
:
R = A + ( x > y? x: y ) * B;
R = A + ( x < y? ( a>b? c: x+c ): y ) * B;
, 2 3 :
(a < b? a: b) = c*x+d; // c*x+d b.
(a < b? a: b < c? b: c) = f(x); :
if (a < b) {
a = f(x);
}
else {
if (b < c) {
b = f(x);
}
else {
c = f(x);
}
!!! if . .
( , throw ). , . :
F1 ( 2, 0x5a, ( F2(2, 0x5a, 1) & ~0x40 ) | (i==j)? 0x03: 0x02, 1 );
'' , , .
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. (IV . . .). , , , , . XIX . , , . , (, ) .
, , .
: , 4 , , 1, .
!, , !, ? .
, , , , , .
6 3, .
: 6 3, 6 2. 6 2, : && .
: , , . .
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: .
: true () false ().
, .
(, ), ! A , . .
A B A B ( ), A && B , . ... .
A B A B ( ), A || B , . ... .
A B (A => B) , » ( , ), , A , . , . , . : ..., , ..., , ...., . , , », », , , ». A =>B ! A || B.
: , , , . , , .
A A B ( , , A , B), , A B . (!A || B) && (A ||!B).
A , !(A) ||!(B), , .
A , !(A) &&!(B), , .
.
, :
!(X && Y) =!X ||!Y
!(X || Y) =!X &&!Y
:
X && (Y || Z) = (X && Y) || (X && Z)
X || (Y && Z) = (X || Y) && (X || Z)
++, , (. 6.3). .
.
A | B | && | || | !B | ! A || B | (!A || B) && (A ||!B) | !(A) ||!(B) | !(A) &&!(B) |
0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 |
0 | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 |
1 | 0 | 0 | 1 | 1 | 0 | 0 | 1 | 0 |
1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 0 |
( ) , : . .
-----------------------------------------------------------------------------------------
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