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善用常量数组往往能简化代码。定义常量数组时无须指明大小，编译器会计算。
下面是两道例题
$WERTYU$（$UVa10082$）
#include
char s[] = "`1234567890-=QWERTYUIOP[]\\ASDFGHJKL;'ZXCVBNM,./";
int main(){
int i, c;
while((c = getchar()) != EOF){
for (i=1; s[i] && s[i]!=c;i++);
if(s[i]) putchar(s[i-1]);
else putchar(c);
}
return 0;
}
回文词（$UVa401$）
输入一个字符串，判断它是否为回文串以及镜像串。输入字符串保证不含数字0。（使用常量数组）
#include
#include
#include
const char* rev = "A 3 HIL JM O 2TUVWXY51SE Z 8 ";
const char* msg[] = {"not a palindrome", "a regular palindrome", "a mirrored string", "a mirrored palindrome"};
char r(char ch) {
if(isalpha(ch)) return rev[ch - 'A'];
return rev[ch - '0' + 25];
}
int main() {
char s[30];
while(scanf("%s", s) == 1) {
int len = strlen(s);
int p = 1, m = 1;
for(int i = 0; i < (len+1)/2; i++) {
if(s[i] != s[len-1-i]) p = 0;
if(r(s[i]) != s[len-1-i]) m = 0;
}
printf("%s -- is %s.\n\n", s, msg[m*2+p]);
}
return 0;
}