题解 | 字符个数统计

#include <stdio.h>
#include <stdbool.h>

int main()
{
    char word;
    bool hash[130] = {false};
    int count = 0;

    word = getchar();
    while (word != '\n')
    {
        hash[word] = true;
        word = getchar();
    }

    for (int i = 0; i < sizeof(hash); i++)
    {
        if (hash[i])
            count++;
    }
    printf("%d\n", count);

    return 0;
}