Sum of Digits in the Minimum Number - Practice Coding Problems

Sum of Digits in the Minimum Number - Problem

Array Math Easy

You're given an integer array nums containing positive integers. Your task is to find the minimum value in the array, calculate the sum of its digits, and then determine if this sum is odd or even.

Return:

0 if the sum of digits is odd
1 if the sum of digits is even

Example: If nums = [12, 34, 7, 18], the minimum is 7. The sum of digits of 7 is just 7 (odd), so return 0.

Input & Output

example_1.py — Basic Case

$ Input: nums = [29, 87, 14, 56]

› Output: 0

💡 Note: The minimum value is 14. Sum of digits: 1 + 4 = 5, which is odd, so return 0.

example_2.py — Even Sum

$ Input: nums = [99, 77, 33, 66, 55]

› Output: 1

💡 Note: The minimum value is 33. Sum of digits: 3 + 3 = 6, which is even, so return 1.

example_3.py — Single Digit

$ Input: nums = [7]

› Output: 0

💡 Note: The minimum (and only) value is 7. Sum of digits is just 7, which is odd, so return 0.

Visualization

Tap to expand

Understanding the Visualization

Survey All Trophies

Walk through all trophies once to find the one with the smallest number

Analyze the Winner

Take the trophy with the minimum number and examine its digits

Count the Digits

Add up all the individual digits on the trophy

Determine Odd/Even

Check if the sum is odd (return 0) or even (return 1)

Key Takeaway

🎯 Key Insight: We only need one pass through the array to find the minimum, then use simple math (% and /) to extract digits efficiently without string conversion.

Time & Space Complexity

Time Complexity

⏱️

O(n + d)

O(n) to find minimum plus O(d) to sum d digits of the minimum number

✓ Linear Growth

Space Complexity

O(1)

Only using constant extra space for variables

✓ Linear Space

Constraints

1 ≤ nums.length ≤ 100
1 ≤ nums[i] ≤ 10⁴
All integers are positive

Asked in

a Amazon 15 ⊞ Microsoft 8 G Google 5 Apple 3

The optimal solution uses a single pass to find the minimum element in O(n) time, then employs mathematical operations (modulo and division) to efficiently extract and sum the digits without string conversion overhead.

Common Approaches

Approach	Time	Space	Notes
✓ One-Pass Linear Solution (Optimal)	O(n + d)	O(1)	Find minimum in one pass, then use math to sum digits efficiently
Brute Force (String Conversion)	O(n²)	O(1)	Find minimum using nested comparisons, convert to string for digit extraction

One-Pass Linear Solution (Optimal) — Algorithm Steps

Iterate through array once to find minimum element
Use modulo 10 to get last digit, division by 10 to remove it
Repeat until all digits are processed and summed
Return 0 if sum is odd, 1 if sum is even

Visualization

Tap to expand

Step-by-Step Walkthrough

Find Minimum

Single pass to find minimum element

Extract Digits

Use modulo and division to get digits

Check Parity

Determine if sum is odd or even

Code -

solution.c — C

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

int sumOfDigits(int* nums, int size) {
    // Find minimum in one pass
    int minimum = nums[0];
    for (int i = 1; i < size; i++) {
        if (nums[i] < minimum) {
            minimum = nums[i];
        }
    }
    
    // Sum digits using math operations
    int digitSum = 0;
    int temp = minimum;
    while (temp > 0) {
        digitSum += temp % 10;
        temp /= 10;
    }
    
    // Return 0 if odd, 1 if even
    return digitSum % 2 == 0 ? 1 : 0;
}

int main() {
    char input[1000];
    fgets(input, sizeof(input), stdin);
    
    // Parse input
    int nums[100];
    int size = 0;
    char* token = strtok(input, "[],\n");
    while (token != NULL) {
        nums[size++] = atoi(token);
        token = strtok(NULL, "[],\n");
    }
    
    printf("%d\n", sumOfDigits(nums, size));
    return 0;
}

Time & Space Complexity

Time Complexity

⏱️

O(n + d)

O(n) to find minimum plus O(d) to sum d digits of the minimum number

✓ Linear Growth

Space Complexity

O(1)

Only using constant extra space for variables

✓ Linear Space

Constraints

1 ≤ nums.length ≤ 100
1 ≤ nums[i] ≤ 10⁴
All integers are positive

28.5K Views

Medium Frequency

~8 min Avg. Time

847 Likes

Ln 1, Col 1

Smart Actions

💡 Explanation

AI Ready

💡 Suggestion Tab to accept Esc to dismiss

// Output will appear here after running code

Code Editor Closed

Click the red button to reopen

Input & Output

Visualization

Time & Space Complexity

Related Problems

Constraints

Common Approaches

One-Pass Linear Solution (Optimal) — Algorithm Steps

Visualization

Code -

Time & Space Complexity

Constraints

Select Compiler