数组读取空格和控制字符

Question

char str[100];    
fgets(str,100,stdin);
int i;
int alpha=0;    
int space=0;
int cntrl=0;
while(str[i])
{
     if(isalpha(str[i]))
     {
        printf("%c is an alphabet\n",str[i]);
        alpha++;
     }
     if(isspace(str[i]))
     {
        printf("%c is a whitespace\n",str[i]);
        space++;
     }
     if(iscntrl(str[i])) 
     {
        printf("%c is a control character\n",str[i]);
        cntrl++;
     }
}

printf("You have %d alphabet\n",alpha);
printf("Your input has %d whitespace\n",space);
printf("Your input has %d control character\n",cntrl);

即使在我没有使用空格之后，它总是显示一个空格也控制字符，我认为这与数组大小有关。我该如何解决？

Answer 1

改变这一行：

while(str[i])

更正为：

while(str[i++])

你的完整代码：

char str[100];    
fgets(str,100,stdin);
int i=0; // initialize here
int alpha=0;    
int space=0;
int cntrl=0;
while(str[i++]) // increment after each loop
{
    if(isalpha(str[i]))
    {
        printf("%c is an alphabet\n",str[i]);
        alpha++;
    }
    if(isspace(str[i]))
    {
        printf("%c is a whitespace\n",str[i]);
        space++;
    }
    if(iscntrl(str[i])) 
    {
        printf("%c is a control character\n",str[i]);
        cntrl++;
    }
}

printf("You have %d alphabet\n",alpha);
printf("Your input has %d whitespace\n",space);
printf("Your input has %d control character\n",cntrl);