4

#include<stdio.h>
#define N 4
int main(){
int a[N] = {2,0,2,3};
char b[N] ={'2','0','2','3'};
int i;

printf("sizeof(int) = %d\n",sizeof(int));
printf("sizeof(char) = %d\n",sizeof(char));
printf("\n");

for(i =0;i<N;++i)
printf("%p:%d\n",&a[i],a[i]);
printf("\n");

printf("a=%p\n",a);
printf("b=%p\n",b);

system("pause");

return 0;
}

 

 

 

 

 

#include <stdio.h>
#define N 2
#define M 3

int main() {
int a[N][M] = {{1, 2, 3}, {4, 5, 6}};
char b[N][M] = {{'1', '2', '3'}, {'4', '5', '6'}};
int i, j;

for (i = 0; i < N; ++i)
for (j = 0; j < M; ++j)
printf("%p: %d\n", &a[i][j], a[i][j]);

printf("\n");

printf("a[0] = %p\n", a[0]);
printf("a[1] = %p\n", a[1]);
printf("\n");

for (i = 0; i < N; ++i)
for (j = 0; j < M; ++j)
printf("%p: %c\n", &b[i][j], b[i][j]);
printf("\n");

printf("b = %p\n", b);
printf("b[0] = %p\n", b[0]);
printf("b[1] = %p\n", b[1]);
printf("\n");

system("pause");
return 0;
}

 

 

2

 

#include <stdio.h>
#include <string.h>

#define N 80

void swap_str(char s1[N], char s2[N]);
void test1();
void test2();

int main() {
printf("测试1: 用两个一维维数组，实现两个字符串交换\n");
test1();

printf("\n测试: 用二维数组，实现两个字符串交换\n");
test2();

return 0;
}

void test1() {
char views1[N] = "hey, C, I hate u.";
char views2[N] = "hey, C, I love u.";

printf("交换前: \n");
puts(views1);
puts(views2);

swap_str(views1, views2);

printf("交换后: \n");
puts(views1);
puts(views2);
}

void test2() {
char views[2][N] = {"hey, C, I hate u.", "hey, C, I love u."};

printf("交换前: \n");
puts(views[0]);
puts(views[1]);

swap_str(views[0], views[1]);

printf("交换后: \n");
puts(views[0]);
puts(views[1]);
}

void swap_str(char s1[N], char s2[N]) {
char tmp[N];

strcpy(tmp, s1);
strcpy(s1, s2);
strcpy(s2, tmp);
}

 

 

 

3

 

#include<stdio.h>
#include<stdlib.h>
#define N 80
int count(char x[]);

int main(){
char words[N+1];
int n;

while(gets(words)!=NULL){
n=count(words);
printf("单词数：%d\n\n",n);
}
system("pause");
return 0;
}
int count(char x[]){
int i;
int word_flag=0;
int number=0;

for(i=0;x[i]!='\0';i++){
if(x[i]==' ')
word_flag=0;
else if(word_flag==0){
word_flag=1;
number++;
}
}
return number;
}

 

 

 

4

 

#include <stdio.h>
#define N 5

//函数声明
void input(int x[],int n);
void output(int x[],int n);
double average(int x[],int n);
void bubble_sort(int x[],int n);

int main(){
int scores[N];
double ave;

printf("录入%d个分数： \n",N);
input(scores,N);

printf("\n输出课程分数： \n");
output(scores,N);

printf("\n课程分数处理：计算均分、排序...\n");
ave = average(scores,N);
bubble_sort(scores,N);

printf("\n输出课程均分：%.2f\n",ave);
printf("\n输出课程分数（高-->低）：\n");
output(scores,N);

system("pause");
return 0;
}

//函数定义
//输入n个整数保存到整型数组x中
void input(int x[],int n){
int i;

for(i=0;i<n;i++)
scanf("%d",&x[i]);
}

//输出整形数组x中n个元素
void output(int x[],int n){
int i;

for(i=0;i<N;i++)
printf("%d",x[i]);
printf("\n");

}

//计算整型数组中n个整数的平均值
double average(int x[],int n){
int i;
double s=0,a;

for(i=0;i<n;i++)
s = s+x[i];
a = s/n;
return a;
}

//对整型数组x中的n个元素降序排序
void bubble_sort(int x[],int n){
int i,j,t;
for(i = 0;i<n;i++){
for(j=0;j<n;j++){
if(x[i]<x[i+1]){
t = x[i];
x[i] = x[i+1];
x[i+1] = t;
}
}
}
}

 

 

 

 

5

 

#include<stdio.h>
#define N 100
void dec2n(int x,int n);
int main(){
int x;
printf("输入一个十进制整数：");
while(scanf("%d",&x)!=EOF){
dec2n(x,2);
dec2n(x,8);
dec2n(x,16);

printf("\n输入一个十进制整数\n");
}
system("pause");
return 0;
}void dec2n(int x, int n){
char s[N]="0123456789ABCDEF";
int a[N],j,i=0;
char q[N];
while(x!=0){
a[i]=x%n;
x=x/n;
i++;
}
i--;
j=0;
while (i>=0){
q[j]=s[a[i]];
j++;
i--;
}
q[j]='\0';
printf("%s\n",q);
}

 

 

 

6

 

#include<stdio.h>
#define N 100
#define M 4

void output(int x[][N],int n);
void rotate_to_right(int x[][N],int n);

int main(){
int t[][N]={{21,12,13,24},
{25,16,47,38},
{29,11,32,54},
{42,21,33,10}};
printf("原始矩阵：\n");
output(t,M);

rotate_to_right(t,M);
printf("变换后矩阵：\n");
output(t,M);

system("pause");
return 0;
}
void output(int x[][N],int n){
int i,j;

for(i=0;i<n;++i){
for(j=0;j<n;++j)
printf("%4d",x[i][j]);
printf("\n");
}
}
void rotate_to_right(int x[][N],int n){
int i,t,j=0;
for(i=0;i<n;i++){
t=x[i][n-1];
for(j=n-1;j>=0;j--){
x[i][j]=x[i][j-1];
}
x[i][0]=t;
}
}

 

7

 

#include<stdio.h>
#include<stdlib.h>
#define N 80
void replace(char x[],char old_char,char new_char);
int main(){
char text[N]="c programming is difficult or not,it is a question.";

printf("原始文本：\n");
printf("%s\n",text);

replace(text,'i','*');

printf("处理后文本：\n");
printf("%s\n",text);

system("pause");
return 0;
}
void replace(char x[],char old_char,char new_char){
int i;
for(i=0;x[i]!='\0';++i)
if (x[i]==old_char)
x[i]=new_char;
}

 

 

 

#include<stdio.h>
#define N 80

int main(){
char str[N],ch;
int i;

printf("输入字符串：");
gets(str);

printf("输入一个字符：");
ch = getchar();

printf("截断处理：。。。。");
i=0;
while(str[i]!='\0'){
if(str[i]==ch)
break;
i++;
}
str[i]='\0';
printf("\n截断处理后字符：%s",str);
system("pause");
return 0;
}

 

8

#include<stdio.h>
#include<string.h>
#define N 5
#define M 20

void bubble_sort(char str[][M],int n);
int main(){
char name[][M]={"Bob","Bill","Joseph","Taylor","George"};
int i;
printf("输出初始名单：\n");
for(i=0;i<N;i++)
printf("%s\n",name[i]);

printf("\n排序中。。。\n");
bubble_sort(name,N);

printf("\n按字典序输出名单：\n");
for(i=0;i<N;i++)
printf("%s\n",name[i]);

system("pause");
return 0;
}
void bubble_sort(char str[][M], int n){

int i,j,k=0;
char tmp[M];
for (i=1;i<n;i++){
for (j=n-1;j>=i;j--){
k=0;
if(str[j][k]==str[j-1][k]){
while( str[j][k]==str[j-1][k] && str[j][k]!='\0' && str[j-1][k]!='\0'){
k++;}
}
if (str[j][k]<str[j-1][k] || str[j][k]=='\0'){

strcpy(tmp, str[j]);
strcpy(str[j], str[j-1]);
strcpy(str[j-1], tmp);
}

}
}
}