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#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <assert.h>

// Declare a union type called 'union Number'.  The type name is 'union Number'.
union Number {
    int    as_int;
    double as_double;
};   // <<<< SEMICOLON!!! <<<<<


int main(int argc, char* argv[]) {

    printf("\nDeclare variable 'n' as 'union Number' and initialize its '.as_double'\n");
    printf("field to 654321.123456.\n");
    union Number n = { .as_double = 654321.123456 };

    printf("n.as_double == %f\n", n.as_double);
    printf("n.as_int    == %d   <<< WRONG\n", n.as_int);

    printf("\nSet the '.as_int' field of variable 'n' to 5.\n");
    n.as_int = 5;
    printf("n.as_int    == %d\n", n.as_int);
    printf("n.as_double == %f    <<< WRONG\n", n.as_double);

    return EXIT_SUCCESS;
}
/* vim: set tabstop=4 shiftwidth=4 fileencoding=utf-8 noexpandtab: */

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