ADVANCED DATA STRUCTURES PROGRAM • LEVEL 19 — FILES AND FILE ORGANIZATION
Build an Inverted Index for Text Records
Learn how to build an inverted index for text records using a clear C program.
PROBLEM UNDERSTANDING
Input and expected output
Sample input
No input required
Sample output
Record IDs: 0 1
COMPLETE C PROGRAM
Complete C implementation
#include <stdio.h>
#include <string.h>
int main(void)
{
const char*records[]={"data structures","advanced data","graph structures"};const char*term="data";printf("Record IDs:");for(int i=0;i<3;i++)if(strstr(records[i],term))printf(" %d",i);putchar('\n');return 0;
}CURRENT STEP
Select Start to walk through the important lines.
SELECTED LINE
No line selected
EXPECTED OUTPUT FOR THE SAMPLE
Record IDs: 0 1
Step 0 of 0
PROGRAM EXPLANATION
Algorithm and explanation
- Read the required input values.
- Associate each term with a postings list of record identifiers containing it.
- Display the computed result.
Associate each term with a postings list of record identifiers containing it.
EFFICIENCY
Time and space complexity
Time complexity
O(total text) to build
Auxiliary space
O(postings)
DEBUGGING CHECKLIST
Common mistakes
Check this
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.