作业练习
1.
#include <stdio.h>
int main(void) {
char ch;
int spare, other, n; //空格，其他字符，换行
spare = other = n = 0;
while ((ch = getchar()) != '#') {
if (ch == ' ')
spare++;
else if (ch == '\n')
n++;
else
other++;
}
printf("spare:%d\nn:%d\nother:%d", spare, n, other);
return 0;
}2.
#include <stdio.h>
int main(void) {
char ch;
int count;
while ((ch = getchar()) != '#'){
printf("%3d ",ch);
count++;
if (count % 8 == 0)
printf("\n");
}
return 0;
}3.
#include <stdio.h>
int main(void) {
int value, count_o, count_e;
float odd, even;
odd = even = count_o = count_e = 0;
while ((scanf("%d", &value)) == 1 && value != 0) {
if (value % 2 == 0) {
odd = odd + value;
count_o++;
} else {
even = even + value;
count_e++;
}
}
if (count_o > 0)
printf("odd average:%.2f count:%2d\n", odd / count_o, count_o);
if (count_e > 0)
printf("even average:%.2f count:%2d\n", even / count_e, count_e);
return 0;
}4.
#include <stdio.h>
int main(void) {
char ch;
int count = 0;
while ((ch = getchar()) != '#'){
if(ch == '.'){
ch = '!';
count++;
} else if (ch == '!'){
printf("%c");
count++;
}
printf("%c",ch);
}
printf("Number:%d",count);
return 0;
}5.
#include <stdio.h>
int main(void) {
char ch;
int count = 0;
while ((ch = getchar()) != '#'){
switch (ch){
case '.':ch='!';count++;
break;
case '!':printf("%c",ch);count++;
break;
}
printf("%c",ch);
}
printf("Number:%d",count);//一共替换了多少次。
return 0;
}6.
#include <stdio.h>
int main(void) {
char ch,ch2,ch3;
//ch3为前一个字符，ch为当前字符，我真没想到。。
int count = 0;
while ((ch=getchar()) != '#'){
ch3=ch2;ch2=ch;
if (ch3 == 'e' && ch == 'i')
count++;
}
printf("%d",count);
return 0;
}7.
#include <stdio.h>
#define WORK_OVERTIME 40
#define RATE1 0.15
#define RATE2 0.20
#define RATE3 0.25
#define WAGE 10.0
#define WAGE_OVERTIME 15.0
#define BREAK1 300.0
#define BREAK2 450.0
#define BASE1 (BREAK1 * RATE1)
#define BASE2 (BASE1 + ((BREAK2 - BREAK1) * RATE2))
int main(void) {
int hr;
double wage,income,tax;
printf("Please enter the hr (q to quit) :");
while ((scanf("%d",&hr)) == 1){
if (hr <= WORK_OVERTIME)
wage = hr * WAGE;
else wage = WORK_OVERTIME * WAGE +((hr - WORK_OVERTIME) * WAGE_OVERTIME);
if (wage <= BREAK1){
tax = wage * RATE1;
}
else if (wage > 300 && wage <= 450 ){
tax = BASE1 + (wage - BREAK1) * RATE2;
}
else tax = BASE2 + (wage - BREAK2) * RATE3;
income = wage - tax;
printf("The wage: %.2f income:%.2lf tax:%.2lf\n", wage, income, tax);
printf("Please enter the hours (q to quit) :");
}
return 0;
}8.
#include <stdio.h>
#define WORK_OVERTIME 40
#define RATE1 0.15
#define RATE2 0.20
#define RATE3 0.25
#define BREAK1 300.0
#define BREAK2 450.0
#define BASE1 (BREAK1 * RATE1)
#define BASE2 (BASE1 + ((BREAK2 - BREAK1) * RATE2))
int main(void) {
int hr,number;
double wage,income,tax,wage2;
printf("------------------------------------------------------------------------\n");
printf("Enter the number number corresponding to the desired pay rate or action:\n");
printf("1) $8.15/hr 2) $9.33/hr\n");
printf("3) $10.00/hr 4) $11.20/hr\n");
printf("5) quit\n");
printf("------------------------------------------------------------------------\n");
printf("Please enter your choise:");
while ((scanf("%d", &number)) == 1){
switch (number){
case 1: wage2 = 8.75;
break;
case 2: wage2 = 9.33;
break;
case 3: wage2 = 10.00;
break;
case 4: wage2 = 11.20;
break;
default:
printf("Please enter the : 1 2 3 4 5 \n");
printf("Please enter your choise:");
continue; //continue使得程序跳过该循环的其余部分
}
if (number == 5) break;
printf("Please enter the hours:");
scanf("%d",&hr);
if (hr <= WORK_OVERTIME)
wage = hr * wage2;
else wage = WORK_OVERTIME * wage2 +((hr - WORK_OVERTIME) * wage2 * 1.5);
if (wage <= BREAK1){
tax = wage * RATE1;
}
else if (wage > 300 && wage <= 450 ){
tax = BASE1 + (wage - BREAK1) * RATE2;
}
else tax = BASE2 + (wage - BREAK2) * RATE3;
income = wage - tax;
printf("The wage: %.2f income:%.2lf tax:%.2lf\n", wage, income, tax);
printf("------------------------------------------------------------------------\n");
printf("Enter the number number corresponding to the desired pay rate or action:\n");
printf("1) $8.15/hr 2) $9.33/hr\n");
printf("3) $10.00/hr 4) $11.20/hr\n");
printf("5) quit\n");
printf("------------------------------------------------------------------------\n");
printf("Please enter your choise:");
}
return 0;
}9.
#include <stdio.h>
//写这题的时候我是懵逼的，只好看了下答案。2333
//解决方式是能被div整除的就不是素数
int main(void) {
int limit;
int num;
int div;
int numisprime; //当其为1的时候num为素数，如果num不是素数时，其变为0
printf("Please enter a positive integer:");
while ((scanf("%d", &limit)) == 1 && limit > 0) {
if (limit > 1)
printf("Here are the prime numbers up through %d\n", limit);
else
printf("No primes.\n");
for (num = 2; num <= limit; num++)
{
for (numisprime = 1, div = 2; (div * div) <= num; div++)
if (num % div == 0)
numisprime = 0;
if (numisprime == 1)
printf("%d is prime.\n", num);
}
printf("Please enter a positive integer (q to quit) :");
}
return 0;
}
10.
#include <stdio.h>
#define RATE1 0.15
#define RATE2 0.28
int main(void) {
int number;
double wage,tax,wage2; //wage工资，tax税收，wage2税金分界点
printf("------------------------------------------------------------------------\n");
printf("Enter the number number corresponding to the desired pay rate or action:\n");
printf("1) Single tax 2) Household tax\n");
//1.单身 2.户主 3.共有 4.离异
printf("3) Married Total tax 4) Married divorced tax\n");
printf("5) quit\n");
printf("------------------------------------------------------------------------\n");
printf("Please enter your choise:");
while ((scanf("%d", &number)) == 1 && number != 5){
switch (number){
case 1: wage2 = 17850; //单身
break;
case 2: wage2 = 23900; //户主
break;
case 3: wage2 = 29750; //已婚，共有
break;
case 4: wage2 = 14875; //已婚，离异
break;
default:
printf("Please enter the : 1 2 3 4 5 \n");
printf("Please enter your choise:");
continue; //continue使得程序跳过该循环的其余部分
}
printf("Please enter the wage:");
scanf("%lf",&wage);
if (wage <= wage2)
tax = wage *RATE1;
else tax = wage2 * RATE1 + ((wage - wage2) * RATE2);
printf("Your tax is :%.2lf\n", tax);
printf("Please enter your choise:");
}
return 0;
}
11.
#include <stdio.h>
#define GOODS1 2.05 //货物1
#define GOODS2 1.15 //货物2
#define GOODS3 1.09 //货物3
#define BREAK1 5
#define BREAK2 20
#define BASE1 6.5
#define BASE2 14
#define DISCOUNT_MONEY 100
#define DISCOUNT 0.05
int main(void) {
int number;
double weight,cost,discount,cost2,goods;
double all;
double a,b,c,w_a,w_b,w_c;
printf("请选择需要购买的货物:\n");
printf("1)洋蓟:2.05/lb\n");
printf("2)甜菜:1.15/lb\n");
printf("3)胡萝卜:1.09/lb\n");
printf("q)退出选购\n");
printf("请输入你的选择:");
while (scanf("%d", &number) == 1 ){
switch (number){
case 1:printf("请输入需要洋蓟的重量:");
scanf("%lf", &a);
break;
case 2:printf("请输入需要甜菜的重量:");
scanf("%lf", &b);
break;
case 3:printf("请输入需要胡萝卜的重量:");
scanf("%lf", &c);
break;
default:printf("输入错误，请输入合适的选项(1,2,3,q):");
continue;
}
w_a = w_a + a;
w_b = w_b + b;
w_c = w_c + c;
a = b = c = 0;
printf("请输入你的选择:");
}
cost = w_a * GOODS1 + w_b * GOODS2 + w_c * GOODS3;
weight = w_a + w_b + w_c;
if (cost >= DISCOUNT_MONEY){
discount = cost * DISCOUNT;
cost = cost * (1 - DISCOUNT);
}
if (weight <= BREAK1)
cost2 = BASE1;
else if (weight > BREAK1 && weight <= BREAK2)
cost2 = BASE2;
else cost2 = BASE2 + ((weight - BREAK2) * 0.5);
printf("所需洋蓟的磅数:%.2lf\n", w_a);
printf("所需甜菜的磅数:%.2lf\n", w_b);
printf("所需胡萝卜的磅数:%.2lf\n", w_c);
printf("订购的总磅数：%.2lf\n", weight);
printf("所需洋蓟的费用:%.2lf\n", w_a * GOODS1);
printf("所需甜菜的费用:%.2lf\n", w_b * GOODS2);
printf("所需胡萝卜的费用:%.2lf\n", w_c * GOODS3);
printf("订单的运输和装卸费用：%.2f\n", cost2);
printf("订单的折扣：%.2f\n", discount);
printf("订单的总费用（包括运输费用，而且还要减去折扣）:%.2f\n",cost + cost2);
return 0;
}