C Exercises: Find length of the longest substring of a given string without repeating characters
C Programming Practice: Exercise-2 with Solution
Write a C program to find length of the longest substring of a given string without repeating characters.
Note:
1) Given string consists of English letters, digits, symbols and spaces.
2) 0 <= Given string length <= 5 * 104
Difficulty: Medium.
Company: Amazon, Google, Bloomberg, Microsoft, Adobe, Apple, Oracle, Facebook and more.
Input String : xyzxyzyy
The longest Substring Length : 3
The longest substring : xyz
Input String : pickoutthelongestsubstring
The longest Substring Length : 8
The longest substring : ubstring
Input String : ppppppppppppp
The longest substring : p
The longest Substring Length : 1
Input String : Microsoft
The longest substring : Micros
The longest Substring Length : 6
C Code:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static int length_of_longest_substring(char *str1)
{
int offset[128];
int substr_max_len = 0;
int len = 0;
int index = 0;
memset(offset, 0xff, sizeof(offset));
while (*str1 != '\0') {
if (offset[*str1] == -1) {
len++;
}
else {
if (index - offset[*str1] > len)
{
len++;
}
else
{
len = index - offset[*str1];
}
}
if (len > substr_max_len)
{
substr_max_len = len;
}
offset[*str1++] = index++;
}
return substr_max_len;
}
int main(void)
{
char *str1 = "xyzxyzyy";
printf("\nOriginal String: %s", str1);
printf("\nLength of the longest substring without repeating characters: %d\n", length_of_longest_substring(str1));
return 0;
}
Sample Output:
Original String: xyzxyzyy Length of the longest substring without repeating characters: 3
Pictorial Presentation:
Flowchart:

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Previous: Write a C programming to get the indices of the two numbers of a given array of integers, such that the sum of the two numbers equal to a specific target.
Next: Write a C program to find the median of the two given sorted arrays which are not empty.
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C Programming: Tips of the Day
Maximum value of int:
In C:
#include <limits.h> then use int imin = INT_MIN; // minimum value int imax = INT_MAX;
or
#include <float.h> float fmin = FLT_MIN; // minimum positive value double dmin = DBL_MIN; // minimum positive value float fmax = FLT_MAX; double dmax = DBL_MAX;
Ref : https://bit.ly/3fi8yk9
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