# How To Wiki

### Site Tools

cs:c_language:boolean_expressions

# Boolean Expressions

Concepts:
Boolean expressions (and `if` statement)

Text:
Some examples regarding boolean expressions, in conjunction with the `if`statement.

Examples have been explained with comments in the code.

Solution:

boolean_expressions.c
```/* Examples regarding boolean expressions */

#include <stdio.h>

int main() {

int res;
int x = 2, y = 3;

/* In C, a number different than 0 is a TRUE value */
if (-10) {
printf("A: True\n");  /* Executed code */
}

/* A false condition in C is the number 0 */
if (0) {
printf("B: True\n");
}else{
printf("B: False\n"); /* Executed code */
}

res = 3+2*5; /* res=13 */
if (res) { /* 13 is a True value */
printf("C: True\n"); /* Executed code */
}

/* res that is equal to 13 is greater than the 7.
The comparison is therefore a TRUE value, but
NOT TRUE = FALSE */
if ( !(res>5+2) ) {
printf("D: True\n");
}else{
printf("D: False\n"); /* Executed code */
}

/* 2 > 5 is FALSE and 3 < 4 is TRUE, i.e,
FALSE OR TRUE = TRUE, therefore the
variable res contain a value different
than 0, in this case it contains the
value 1 */
res = 2 > 5 || 3 < 4; /* 0 OR 1 */
printf("E: %d\n", res); /* Print "E: 1" */

/* x=2; y=3;
2 >= 3 is FLASE, 3==3 is TRUE, 2!=3 is FALSE
Analizing the boolean expression:
(FALSE AND TRUE) OR NOT TRUE = FALSE OR FALSE = FALSE,
therefore the variable res contains a 0 */
res = (x >= y && x+1==y) || !(x!=y);
printf("F: %d\n", res);

return 0;
}```

Output:
The output of this program is:

```A: True
B: False
C: True
D: False
E: 1
F: 0```

If you found any error, or if you want to partecipate to the editing of this wiki, please contact: admin [at] skenz.it

You can reuse, distribute or modify the content of this page, but you must cite in any document (or webpage) this url: https://www.skenz.it/cs/c_language/boolean_expressions
/web/htdocs/www.skenz.it/home/data/pages/cs/c_language/boolean_expressions.txt · Last modified: 2020/11/26 23:18 (external edit)