Question

how can you count the number of different letters there are in a word in C programming?

Answer 1

Create array of size 52 . if letter is lower case increate at first 26 position like a at 0,b at 1. Silipar to that,if letter is uppercase increament from 26,like A at26,B at 27...

Code

#include<stdio.h>

int main()
{
    char c[]="samplecheck"; //sample string
    int s[52];
    for(int i=0;i<52;i++) //set all elements to 0
        s[i]=0;
    for(int i=0;i<strlen(c);i++)
    {
        if(islower(c[i])) //if lower increase from position 0-25
        {
            s[(int)c[i]-97]++;
        }
        if(isupper(c[i])) //if upper increase from position 26-51
        {
            s[(int)c[i]-39]++;
        }
    }
    int tot=0;
    for(int i=0;i<52;i++)
    {
        if(s[i]!=0) // if not zero the letter is presented in the word
            tot+=1;
    }
    printf("there is %d different letters in the word %s",tot,c);
    return 0;
}

Terminal Work

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