Answers for "count number of characters in a string"

count letter in string

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

int main() {
    char c;
    char s[100];
    scanf("%c", &c);
    scanf("%s", s);
    int count = 0;
    int len = strlen(s);
    for (int i = 0; i < len; i++) {
        if (s[i] == c) {
            count++;
        }
    }
    printf("%d", count);
    return 0;
}

count characters in string

# count characters iterative
def count_chars(s)
  count = Hash.new(0)
  s.split("").each do |x|
    count[x] += 1
  end
  count
end

# count characters functional
s.chars.map {|c| [c, s.chars.count(c)] }.to_h