输入三行文本每行最多100个字符，计算三行文本字母数并输出结果，在两列中显示结果，无需处理特殊字符，基本字母即可，具体样例如下

Question

Give a string (max 100 characters) > Hello World
Give a string (max 100 characters) > It is a nice day
Give a string (max 100 characters) > Hope you are fine
Alphabet Count
a 3
b 0
c 1
d 2
e 5
f 1
g 0
h 2
i 4
j 0
k 0
l 3
m 0
n 2
o 4
p 1
q 0
r 2
s 1
t 1
u 1
v 0
w 1
x 0
y 2
z 0

Answer 1

#include <stdio.h>
int main()
{
    char str[3][101];
    int i,j;
    int sum[26];
    for(i=0;i<26;i++)
        sum[i]=0;
    for (i=0;i<3;i++)
    {
        printf("Give a string (max 100 characters) > ");
        gets(str[i]);
    }
    for (i=0;i<3;i++)
    {
        j=0;
        while(str[i][j])
        {
            if(str[i][j]>='a' && str[i][j]<='z')
                sum[str[i][j]-'a']++;
            else if(str[i][j]>='A' && str[i][j]<='Z')
                sum[str[i][j]-'A']++;
            j++;
        }
    }
    for (i=0;i<26;i++)
    {
        printf("%c %d\n",'a'+i,sum[i]);
    }
    return 0;
}