C PROGRAMMING PROGRAM • STRUCTURES, UNIONS & ENUMS

Store Flags Using Structure Bit-Fields

Learn how to store flags using structure bit-fields using a clear C program.

AdvancedBit-fieldPacked flagsUnsigned members

PROBLEM UNDERSTANDING

Input and expected output

Sample input

No input required

Sample output

ready=1 error=0 mode=2

COMPLETE C PROGRAM

Complete C implementation

#include <stdio.h>

struct Status {
    unsigned ready : 1;
    unsigned error : 1;
    unsigned mode : 2;
};

int main(void)
{
    struct Status status = {1, 0, 2};
    printf("ready=%u error=%u mode=%u\n", (unsigned) status.ready,
           (unsigned) status.error, (unsigned) status.mode);
    return 0;
}

CURRENT STEP

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EXPECTED OUTPUT FOR THE SAMPLE

ready=1 error=0 mode=2

0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

Read the required input values.
Assign a precise bit width to small unsigned flags and access them like structure members.
Display the computed result.

Assign a precise bit width to small unsigned flags and access them like structure members.

EFFICIENCY

Time and space complexity

Time complexity

O(1)

Auxiliary space

O(1)

DEBUGGING CHECKLIST

Common mistakes

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Use the correct format specifier for every variable.

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Initialize variables before using their values.

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Check braces, semicolons and input order carefully.

Try it yourself

Practice: Run the program with the sample input, predict its output, and then test one boundary case of your own.