Boolean type

 

C

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When any scalar value is converted to _Bool, the result is 0 if the value compares equal to 0; otherwise, the result is 1.

Notes

NaNs do not compare equal to 0 and thus convert to 1.

Example

Run this code

#include <stdio.h>
 
int main(void)
{
    _Bool a = 0.0;
    _Bool b = 8;
    _Bool c = 0.0/0.0;
 
    printf("%d\n", a);
    printf("%d\n", b);
    printf("%d\n", c);
 
    return 0;
}

Possible output:

0
1
1