#include<stdio.h>
#define N 4
int main(){
int x[N]={1,9,8,4};
int i;
int *p;
for(i=0;i<N;i++){
printf("%d",x[i]);
} printf("\n");
for(p=x;p<x+N;++p){
printf("%d",*p);
} printf("\n");
p=x;
for(i=0;i<N;i++){
printf("%d",*(p+i) );
} printf("\n");
for(i=0;i<N;i++){
printf("%d",p[i]);
} printf("\n");
return 0;
}
#include <stdio.h>
#define N 80
int func(char *);
int main()
{
char str[80];
while (gets(str) != NULL)
{
if (func(str))
printf("yes\n");
else
printf("no\n");
}
return 0;
}
int func(char*str){
char *begin,*end;
begin=end=str;
while(*end)
end++;
end--;
while(begin<end){
if(*end!=*begin)
return 0;
else{
begin++;
end--;
}
}
return 1;
}
#include <stdio.h>
int main(){
int x[2][4]={{1,9,8,4},{2,0,4,9}};
int i,j;
int *p;
int (*q)[4];
for(i=0;i<2;++i){
for(j=0;j<4;++j){
printf("%d",x[i][j]);
}printf("\n");
}
for(p=&x[0][0],i=0;p<&x[0][0]+8;++p,++i){
printf("%d",*p);
if((i+1)%4==0)
printf("\n");
}
for(q=x;q<x+2;++q){
for(j=0;j<4;++j)
printf("%d",*(*q+j));
printf("\n");
}
return 0;
}
#include <stdio.h>
#include <string.h>
#define N 80
int main()
{
char *s1 = "Learning makes me happy";
char *s2 = "Learning makes me sleepy";
char *tem;
printf("sizeof(s1) vs. strlen(s1): \n");
printf("sizeof(s1) = %d\n", sizeof(s1));
printf("strlen(s1) = %d\n", strlen(s1));
printf("\nbefore swap: \n");
printf("s1: %s\n", s1);
printf("s2: %s\n", s2);
printf("\nswapping...\n");
tem=s1; //指针直接用
s1=s2;
s2=tem;
printf("\nafter swap: \n");
printf("s1: %s\n", s1);
printf("s2: %s\n", s2);
return 0;
}
#include<stdio.h>
void str_cpy(char *target,const char *source);
void str_cat(char *str1,char *str2);
int main(){
char s1[80],s2[20]="1984";
str_cpy(s1,s2);
puts(s1);
str_cat(s1,"Animal Farm");
puts(s1);
return 0;
}
void str_cpy(char *target,const char *source){
while(*target++=*source++)
;
}
void str_cat(char *str1,char *str2){
while(*str1)
str1++;
while(*str1++=*str2++)
;
}
#include <stdio.h>
#define N 80
void func(char *);
int main()
{
char s[N];
while (scanf("%s", s) != EOF)
{
func(s);
puts(s);
}
return 0;
}
void func(char *str){
int i=0;
char *p1,*p2,*p;
p=p1=p2=str;
while(*p1=='*')
p1++;
while(*p2)
p2++;
p2--;
while(p<p1)
{
str[i]=*p;
p++;
i++;
}
while(p<=p2){
if(*p!='*')
{ str[i]=*p;
i++;
}
p++;
}
while(*p !='\0'){
str[i]=*p;
p++;
i++;
}
str[i]='\0';
}
#include <stdio.h>
#include <string.h>
void sort(char *name[], int n);
int main()
{
char *course[4] = {"C Program",
"C++ Object Oriented Program",
"Operating System",
"Data Structure and Algorithms"};
int i;
sort(course, 4);
for (i = 0; i < 4; i++)
printf("%s\n", course[i]);
return 0;
}
void sort(char *name[], int n){
int i,j;
char *tmp;
for(i=0;i<n-1;++i){
for(j=0;j<n-1-i;++j){
if(strcmp(name[j],name[j+1])>0){
tmp=name[j]; //交换地址
name[j]=name[j+1];
name[j+1]=tmp;
}
}
}
}
#include <stdio.h>
#include <string.h>
void sort(char *name[], int n);
int main()
{
char *course[4] = {"C Program",
"C++ Object Oriented Program",
"Operating System",
"Data Structure and Algorithms"};
int i;
sort(course, 4);
for (i = 0; i < 4; i++)
printf("%s\n", course[i]);
return 0;
}
void sort(char *name[], int n){
int i,j,k;
char *tmp;
for(i=0;i<n-1;++i){
for(j=0;j<n-1-i;++j){
k=i;
for(j=i+1;j<n;j++)
{ if(strcmp(name[j],name[k])<0)
k=j;
}
//选择排序
if(k!=i){
tmp=name[i];
name[i]=name[k];
name[k]=tmp;
}
}
}
}
#include <stdio.h>
#include <string.h>
#define N 5
int check_id(char *str); // 函数声明
int main()
{
char *pid[N] = {"31010120000721656X",
"330106199609203301",
"53010220051126571",
"510104199211197977",
"53010220051126133Y"};
int i;
for (i = 0; i < N; ++i)
if (check_id(pid[i])) // 函数调用
printf("%s\tTrue\n", pid[i]);
else
printf("%s\tFalse\n", pid[i]);
return 0;
}
// 函数定义
// 功能: 检查指针str指向的身份证号码串形式上是否合法。
// 形式合法，返回1，否则，返回0
int check_id(char *str)
{ if(*(str+18)!='\0'||*(str+17)=='\0')
return 0;
int i=0;
while((*(str+i)>='0'&&*(str+i)<='9')||*(str+i)=='X')
i++;
if(i==18)
return 1;
else
return 0;
}
#include <stdio.h>
#define N 80
void encoder(char *s); // 函数声明
void decoder(char *s); // 函数声明
int main()
{
char words[N];
printf("输入英文文本: ");
gets(words);
printf("编码后的英文文本: ");
encoder(words); // 函数调用
printf("%s\n", words);
printf("对编码后的英文文本解码: ");
decoder(words); // 函数调用
printf("%s\n", words);
return 0;
}
/*函数定义
功能：对s指向的字符串进行编码处理
编码规则：
对于a~z或A~Z之间的字母字符，用其后的字符替换; 其中，z用a替换，Z用A替换
其它非字母字符，保持不变
*/
void encoder(char *s)
{
while(*s){
if((*s>='a'&&*s<'z')||(*s>='A'&&*s<'Z'))
*s=*s+1;
else if(*s=='z')
*s='a';
else if(*s=='Z')
*s='A';
s++;}
}
/*函数定义
功能：对s指向的字符串进行解码处理
解码规则：
对于a~z或A~Z之间的字母字符，用其前面的字符替换; 其中，a用z替换，A用Z替换
其它非字母字符，保持不变
*/
void decoder(char *s)
{
while(*s){
if((*s>'a'&&*s<='z')||(*s>'A'&&*s<='Z'))
*s=*s-1;
else if(*s=='a')
*s='z';
else if(*s=='A')
*s='Z';
s++;}
}
