C Exercises: Find the element(s) which occurs most frequently in a given sequence

Last update on September 19 2025 12:44:55 (UTC/GMT +8 hours)

Find the most frequently occurring number in a sequence

Write a C program that reads a sequence of integers and finds the element that occurs most frequently.

Sample Solution:

C Code:

#include <stdio.h>
#include<stdlib.h>
#include<math.h>
#include<string.h>

int main(void) {
  int in;
  int nums[101] = {0}; // Initialize an array to store frequency of each number (from 1 to 100)
  int i;
  int max_val = 0; // Variable to keep track of the maximum frequency

  printf("\nInput the terms of the sequence:\n");

  while (scanf("%d", &in) != EOF) // Keep reading numbers until end of input (EOF)
    nums[in]++; // Increment the frequency count for the input number

  // Find the maximum frequency
  for (i = 1; i <= 100; i++) {
    if (max_val < nums[i])
      max_val = nums[i];
  }

  printf("Mode values of the said sequence in ascending order:\n");

  // Print numbers that have the maximum frequency
  for (i = 1; i <= 100; i++) {
    if (max_val == nums[i])
      printf("%d\n", i);
  }

  return 0; // End of the program
}

Sample Output:


Input the terms of the sequence:
5
2
4
6
8
10
^Z
Mode values of the said sequence in ascending order:
2
4
5
6
8
10

Flowchart:

C Programming Flowchart: Find the element(s) which occurs most frequently in a given sequence.

For more Practice: Solve these Related Problems:

Write a C program to read a sequence of integers and determine the mode using arrays for frequency counts.
Write a C program to compute the most frequently occurring number by sorting the array first and then scanning.
Write a C program to use a hash table (array-based) approach to track frequency and find the mode.
Write a C program to determine and print the mode(s) of a sequence with proper handling of ties.

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