还将大写转换为小写进行计数

Question

I have a code that I am supposed to make it go through a list of names and count how many times a letter is used. So far it works for lower case but how do I implement upper case into the picture. I greatly appreciate the help.

/*                                                                              
 * Search through each character in s,                                          
 * which is array containing n strings,                                         
 * and update the global count array                                            
 * with the correct character counts.                                           
 * Note: check the examples to see                                              
 * if the counts should be case                                                 
 * sensitive or case insensitive.                                               
 */
void letterCount(char * s[], int n){
  //Implement this function                                                     
  int c = 0,x,i;
  char p = 'a', j = 'z', A = 'A', Z = 'Z';
  while (c<n) {
    for(i=0;s[c][i]!='\0';i++){
      if (s[c][i] >= p && s[c][i] <= j ){
        x = s[c][i] - 'a';
        count[x]++;
      }
      c++;
    }
  }
}

Answer 1

You can set a criteria for casing of letters, ie, only use lower case or upper case letters. Convert the contents of character array to lower case(by aading 32 to each character's value(ASCII VALUE)) then call letterCount function. Or use strlwr to convert string to lower case.

Answer 2

You can use ascii values like this: count1[] for az and count2[] for AZ

if((s[c][i]  >= 97 && s[c][i] <= 122))
{
x = s[c][i] - 'a';
    count1[x]++;
}


if( (s[c][i] >= 65 && s[c][i]  <= 90)))
{
x = s[c][i] - 'A';
    count2[x]++;
}