全志科技校园招聘笔试题-------编程：
题目：给定字符串''just do it !'',将其转化为大写"JUST DO IT!"
方法一：
/*
*
* 给定一组字符串"just do it!"，将其变成全部大写"JUST DO IT!"
* 方法一：判断字符串范围，对 >=‘a’ && <='z' 的字符串进行转换，即 += 'A'-'a'
*/
#include
#include
#define STR_CHANGE 'A'-'a'
void main()
{
int i=0;
int str_length=0;
/*
* 使用字符数组的方法保存字符串，如果使用字符指针的形式(如下)，程序会出错
* 因为，char *string形式的字符串是只读的，不允许对字符串的字符进行修改
* (只能修改指针变量str的值，使其指向其它字符串)
* char *str="just do it!";
*/
char str[20]="just do it!";
printf("before:%s\n",str);
str_length=strlen(str);
for(i=0;i
{
printf("before: ASCII is %3ld char is %c ",str[i],str[i]); //为了突出比较结果转换前打印出ASCII码值和对应字符
if(str[i] >= 'a' && str[i] <= 'z')
{
str[i] += STR_CHANGE;
}
printf("\tafter: ASCII is %3ld char is %c\n",str[i],str[i]); //为了突出比较结果转换后打印出ASCII码值和对应字符
}
printf("after:%s\n",str);
}
方法二：
/*
*
*给定一组字符串"just do it!"，将其变成全部大写"JUST DO IT!"
*方法二：使用函数toupper 引用头文件 ctype.h
*/
#include
#include
#include
void main()
{
int i=0;
int str_length=0;
char str[20]="just do it!";
printf("before:%s\n",str);
str_length=strlen(str);
for(i=0;i
{
printf("before: ASCII is %3ld char is %c ",str[i],str[i]); //为了突出比较结果转换前打印出ASCII码值和对应字符
if(str[i] >= 'a' && str[i] <= 'z')
{
str[i] = toupper(str[i]);
}
printf("\tafter: ASCII is %3ld char is %c\n",str[i],str[i]); //为了突出比较结果转换后打印出ASCII码值和对应字符
}
printf("after:%s\n",str);
}
/*
*附录：
*ctype.h 中 toupper()函数具体方法
*int toupper(int char)
*{
*return char+'A'-'a';
* }
*
*
*ctype.h 中 tolower()函数具体方法
*int tolower(int char)
*{
*return char+'a'-'A';
* }
*/
运行结果：
before:just do it!
before: ASCII is 106 char is j after: ASCII is 74 char is J
before: ASCII is 117 char is u after: ASCII is 85 char is U
before: ASCII is 115 char is s after: ASCII is 83 char is S
before: ASCII is 116 char is t after: ASCII is 84 char is T
before: ASCII is 32 char is after: ASCII is 32 char is
before: ASCII is 100 char is d after: ASCII is 68 char is D
before: ASCII is 111 char is o after: ASCII is 79 char is O
before: ASCII is 32 char is after: ASCII is 32 char is
before: ASCII is 105 char is i after: ASCII is 73 char is I
before: ASCII is 116 char is t after: ASCII is 84 char is T
before: ASCII is 33 char is ! after: ASCII is 33 char is !
after:JUST DO IT!
方法三：
使用strupr函数
原型：extern char *strupr(char *s);
用法：#include
功能：将字符串s转换为大写形式
说明：只转换s中出现的小写字母，不改变其它
字符。返回指向s的
指针。
兼容性说明：
strupr不是标准C库函数，只能在VC中使用。在linux gcc环境下需要自行定义这个函数。
/*
*
*给定一组字符串"just do it!"，将其变成全部大写"JUST DO IT!"
*方法三：使用函数strupr 引用头文件 string.h
*/
#include
#include
#include
void main()
{
char str[20]="just do it!";
printf("before:%s\n",str);
printf("change to upper :%s\n",strupr(str));
printf("change to lower :%s\n",strlwr(str));
printf("after:%s\n",str);
}
