Maximum Value of a String in an Array

Maximum Value of a String in an Array - Problem

Array String Easy

The value of an alphanumeric string can be defined as:

The numeric representation of the string in base 10, if it comprises of digits only.
The length of the string, otherwise.

Given an array strs of alphanumeric strings, return the maximum value of any string in strs.

Input & Output

Example 1 — Mixed String Types

$ Input: strs = ["alic3","bob","3","4","00000"]

› Output: 5

💡 Note: "alic3" has mixed characters, value = length = 5. "bob" has letters, value = length = 3. "3" is digits only, value = 3. "4" is digits only, value = 4. "00000" is digits only, value = 0. Maximum value is 5.

Example 2 — All Digit Strings

$ Input: strs = ["1","01","001","0001"]

› Output: 1

💡 Note: All strings contain only digits. "1" = 1, "01" = 1, "001" = 1, "0001" = 1. Maximum value is 1.

Example 3 — Large Numbers vs Length

$ Input: strs = ["999","abcdefghijk"]

› Output: 999

💡 Note: "999" is digits only, value = 999. "abcdefghijk" has letters, value = length = 11. Maximum value is 999.

Constraints

1 ≤ strs.length ≤ 100
1 ≤ strs[i].length ≤ 9
strs[i] consists of only lowercase English letters and digits.

Visualization

Tap to expand

Asked in

G Google 15 a Amazon 12

The key insight is to distinguish between pure digit strings (use numeric value) and mixed strings (use length). Best approach uses built-in string validation methods for clean, efficient code. Time: O(n×m), Space: O(1).

Common Approaches

Approach	Time	Space	Notes
✓ Single Pass with Value Calculation	O(n × m)	O(1)	Iterate through each string, calculate its value, and track maximum
Built-in String Methods	O(n × m)	O(1)	Use language built-in methods for digit checking to optimize performance

Single Pass with Value Calculation — Algorithm Steps

Step 1: Initialize maximum value to 0
Step 2: For each string, check if it's all digits
Step 3: Calculate value (numeric or length) and update maximum

Visualization

Tap to expand

Step-by-Step Walkthrough

Check String Type

Determine if string contains only digits

Calculate Value

Convert to number or use length

Update Maximum

Keep track of highest value seen

Code -

solution.c — C

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

int isDigitsOnly(const char* s) {
    for (int i = 0; s[i]; i++) {
        if (!isdigit(s[i])) return 0;
    }
    return 1;
}

int solution(char strs[][100], int n) {
    int maxValue = 0;
    
    for (int i = 0; i < n; i++) {
        int value;
        if (isDigitsOnly(strs[i])) {
            value = atoi(strs[i]);
        } else {
            value = strlen(strs[i]);
        }
        if (value > maxValue) {
            maxValue = value;
        }
    }
    
    return maxValue;
}

int main() {
    char line[1000];
    fgets(line, sizeof(line), stdin);
    
    char strs[100][100];
    int n = 0;
    
    char* token = strtok(line, "[,]\"");
    while (token != NULL && n < 100) {
        if (strlen(token) > 0 && strcmp(token, " ") != 0 && strcmp(token, "\n") != 0) {
            strcpy(strs[n], token);
            n++;
        }
        token = strtok(NULL, "[,]\"");
    }
    
    int result = solution(strs, n);
    printf("%d\n", result);
    
    return 0;
}

Time & Space Complexity

Time Complexity

⏱️

O(n × m)

n strings, each requiring m character checks for digit validation

✓ Linear Growth

Space Complexity

O(1)

Only using variables to track maximum value

✓ Linear Space

12.0K Views

Medium Frequency

~8 min Avg. Time

456 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

Constraints

Visualization

Related Problems

Common Approaches

Single Pass with Value Calculation — Algorithm Steps

Visualization

Code -

Time & Space Complexity

Select Compiler