加密字符串小写字母循环后错两位（加密字符串,小写字母循环后错两位）
加密字符串小写字母循环后错两位（加密字符串,小写字母循环后错两位）
#include "stdio.h"
int main()
{
char a[100];
int b;
printf("请输入字符串：");
scanf("%s",a);
for(b=0;a[b]!='\0';b++)
{
if(a[b]='a'a[b]='x'||a[b]='A'a[b]='X')
a[b]+=2;
else if(a[b]=='y'||a[b]=='z'||a[b]=='Y'||a[b]=='Z')
a[b]-=24;
}
printf("加密后的字符串：%s\n",a);
}
#include stdio.h
#include stdlib.h
#include string.h
#define MAX_FILE_NAME 128
#define MAX_STRING_SIZE 256
void encrypt(void);
void decode(void);
void upper(void);
void lower(void);
void fix(void);
int main(int argc, char **argv)
{
int command=1;
while(command!=0)
{
printf("%-16s%-16s%-16s%-16s%-16s%-16s\n","1.encrypt","2.decode","3.to upper","4.to lower","5.auto fix","0.exit");
printf("enter commond\'s number: ");
scanf("%d",command);
switch(command)
{
case 1: encrypt(); break;
case 2: decode(); break;
case 3: upper(); break;
case 4: lower(); break;
case 5: fix(); break;
case 0: break;
}
}
return 0;
}
void encrypt(void)
{
char source[MAX_FILE_NAME];
char destination[MAX_FILE_NAME];
printf("enter the file\'s path you want to encrypt: ");
scanf("%s",source);
printf("enter the path you want to save the result: ");
scanf("%s",destination);
FILE *input=fopen(source,"r");
if(input==NULL)
{
printf("open file fail\n");
system("pause");
exit(1);
}
FILE *output=fopen(destination,"w");
if(output==NULL)
{
printf("create file fail\n");
system("pause");
exit(1);
}
int inch=fgetc(input);
while(!feof(input))
{
if(inch='a')
fputc((char)('a'+(inch+4)%'a'),output);
else
fputc((char)('A'+(inch+4)%'A'),output);
inch=fgetc(input);
}
fclose(input);
fclose(output);
printf("complete\n");
}
void decode(void)
{
char source[MAX_FILE_NAME];
char destination[MAX_FILE_NAME];
printf("enter the file\'s path you want to encrypt: ");
scanf("%s",source);
printf("enter the path you want to save the result: ");
scanf("%s",destination);
FILE *input=fopen(source,"r");
if(input==NULL)
{
printf("open file fail\n");
system("pause");
exit(1);
}
FILE *output=fopen(destination,"w");
if(output==NULL)
{
printf("create file fail\n");
system("pause");
exit(1);
}
int inch=fgetc(input);
while(!feof(input))
{
if(inch='a')
fputc((char)('a'+(inch+22)%'a'),output);
else
fputc((char)('A'+(inch+22)%'A'),output);
inch=fgetc(input);
}
fclose(input);
fclose(output);
printf("complete\n");
}
void upper(void)
{
char input[MAX_STRING_SIZE];
printf("input a sentence: ");
scanf("%s",input);
char mode;
fflush(stdin);
printf("Do you want to convert all character to uppercase? (y/n): ");
scanf("%c",mode);
if(mode=='y')
printf("%s\n",strupr(input));
else
{
char *temp=strlwr(input);
int length=strlen(temp);
int j=length-1;
while(j=0)
{
if(temp[j]=='.')
if(j+1length)
if(temp[j+1]='a')
temp[j+1]-=32;
j--;
}
printf("%s\n",temp);
}
}
void lower(void)
{
char input[MAX_STRING_SIZE];
printf("input a sentence: ");
scanf("%s",input);
char *temp=strlwr(input);
int length=strlen(temp);
int j=length-1;
while(j=0)
{
if(temp[j]=='.')
if(j+1length)
if(temp[j+1]='a')
temp[j+1]-=32;
j--;
}
if(length!=0)
if(temp[0]='a')
temp[0]-=32;
printf("%s\n",temp);
}
void fix(void)
{
char input[MAX_STRING_SIZE];
char output[MAX_STRING_SIZE];
printf("input a sentence: ");
fflush(stdin);
gets(input);
int length=strlen(input);
if(input[length-1]!='.')
input[length]='.',length++;
int current=0,patt=0;
if(length)
output[current++]=toupper(input[patt++]);
while(pattlength)
{
if(input[patt]==','||input[patt]=='.')
{
int mode=0;
if(input[patt]=='.')
mode=1;
output[current++]=input[patt++];
output[current++]=' ';
while(pattlength(input[patt]==' '||input[patt]=='\t'))
patt++;
if(pattlengthmode)
output[current++]=toupper(input[patt++]);
}
else if(input[patt]==' '||input[patt]=='\t')
{
output[current++]=' ';
while(pattlength(input[patt]==' '||input[patt]=='\t'))
patt++;
}
else
output[current++]=input[patt++];
}
printf("%s\n",output);
}
char jiami(char ch)
{
/* 加密小写字符，其他字符不管 */
if(ch='a' ch='z')
return ('a' + (ch-'a'+5) % 26);
else
return ch;
}
