ADVANCED DATA STRUCTURES PROGRAM • LEVEL 18 — ADVANCED HASHING

Equalize Probe Distances with Robin Hood Hashing

Learn how to equalize probe distances with robin hood hashing using a clear C program.

AdvancedCollision resolutionHash-table design

PROBLEM UNDERSTANDING

Input and expected output

Sample input

No input required

Sample output

3:10(0) 4:17(1) 5:24(2) 6:31(3)

COMPLETE C PROGRAM

Complete C implementation

#include <stdio.h>

int main(void)
{
    int table[7]={0},distance[7]={0},keys[]={10,17,24,31};
    for(int k=0;k<4;k++){int key=keys[k],dist=0,slot=key%7;while(table[slot]){if(distance[slot]<dist){int t=table[slot];table[slot]=key;key=t;t=distance[slot];distance[slot]=dist;dist=t;}slot=(slot+1)%7;dist++;}table[slot]=key;distance[slot]=dist;}
    for(int i=0;i<7;i++){if(table[i])printf("%d:%d(%d) ",i,table[i],distance[i]);}
    putchar('\n');return 0;
}

CURRENT STEP

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SELECTED LINE

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EXPECTED OUTPUT FOR THE SAMPLE

3:10(0) 4:17(1) 5:24(2) 6:31(3)

0%Step 0 of 0

PROGRAM EXPLANATION

Algorithm and explanation

Read the required input values.
Let a farther-travelled key steal a slot from a key with a smaller probe distance.
Display the computed result.

Let a farther-travelled key steal a slot from a key with a smaller probe distance.

EFFICIENCY

Time and space complexity

Time complexity

Average O(1)

Auxiliary space

O(table size)

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.