C - primer - plus（第五版）习题答案(8)

printf(\); scanf(\,&score);

printf(\); grade = getchar();

输入分数100后，回车把分数返回给程序，换行符同时被发送，成为下一个输入字符被读取到grade中作为等级的值。添加代码在获取字符输入之前剔除换行字符。

int score; char grade;

printf(\); scanf(\,&score); while(getchar() != '\\n')

continue;

printf(\); grade = getchar();

编程练习：

1.#include

int main(void) { }

2.#include

int main(void) {

int count = 0; char ch;

while((ch = getchar()) != EOF) {

if(ch == '\\n') { }

elseif(ch == '\\t')

printf(\,'\\t');

printf(\,ch+64,ch); elseif(ch < 32)

printf(\,'\\n'); printf(\); count = -1;

int count = 0;

while(getchar() != EOF)

count++;

printf(\, count); return 0;

}

}

else

printf(\,ch,ch); count++;

if(0 == count)

printf(\);

return 0;

3.#include

#include

int main(void) { }

4.#include

int lower_count = 0; int upper_count = 0; char ch;

while((ch = getchar()) != EOF) { }

printf(\,lower_count , upper_count); return 0;

if(islower(ch))

lower_count++; upper_count++;

elseif(isupper(ch))

#include

int main(void) {

char ch;

int count_ch = 0; int count_word = 0; bool word_flag = true; double aver;

while((ch = getchar()) != EOF) {

if(ispunct(ch)) {

word_flag = false; continue; if(word_flag)

}

}

}

count_word++;

if( ch == ' ') { }

if(ch == '\\n')

continue;

count_ch++;

word_flag = true; continue;

aver = ((double)count_ch)/count_word;

printf(\,aver); return 0;

#include #include int main(void) { int ch;

float count=0.0; int w_count,l_count; w_count=l_count=0; printf(\来吧:\\n\); while((ch=getchar())!=EOF){

if(ispunct(ch))

continue;

if (isalpha(ch))

l_count++; else

w_count++; }

if (w_count==0)

w_count=1; //没办法，下面的运算中总不能让分母为啊，那会报错的。 count=(float)l_count/w_count;

printf(\你共输入%d个单词，%d个字母，平均每个单词用字母%.2f个。\,w_count,l_count,count); return 0; }

5.#include

int main(void) {

int guess = 50;

}

char response; int up = 101; int down = 0;

printf(\);

printf(\printf(\); printf(\,guess); while((response = getchar()) != 'y') { }

printf(\); return 0;

if(response == 'b') { }

elseif(response == 's') { } else { }

while(getchar() != '\\n')

continue;

printf(\); continue; down = guess;

guess = guess + (up - guess) / 2; printf(\,guess); up = guess;

guess = guess - (guess - down) / 2; printf(\,guess);

is smaller.\\n\);

6.#include #include char get_first(void);

int main(void) {

char ch;

while((ch =get_first()) != EOF) {

putchar(ch);

}

}

printf(\);

return 0;

char get_first(void) { }

7.#include

int ch;

while(isspace(ch = getchar()))

continue; continue;

while(getchar() != '\\n') return ch;

#include

char get_char(void);

#define TIME 40//加班 #define ADD 1.5

#define LIMIT1 300//税率 #define RATE1 0.15 #define LIMIT2 150 #define RATE2 0.20 #define RATE3 0.25

int main(void) {

while(1) {

printf(\

double hours,total_wages,taxes,wages,base;

printf(\printf(\); printf(\); printf(\);

printf(\**************\\n\);

**************\\n\);

action:\\n\);