对txt文件中读取的字母进行排序

//运用到了文件读取，数值交换，动态数组，冒泡排序等知识点

#include "stdlib.h"

void swap(char *a,char *b);

int main(){
//读取文件信息
FILE *fp = NULL;
fp = fopen("d:\\a.txt","rt");

int i,j,r;
int count=0;
char *dataArray;
char ch;
dataArray = (char*)malloc(sizeof(char));
while(!feof(fp)){
ch = fgetc(fp);
if(-1 != ch){
printf("%c",ch);
dataArray[count] = ch;
count++;
}
}
printf("\n");
//冒泡排序

for(i=0;i<count;i++){
for(j=i+1;j<count;j++){
if(dataArray[i]>dataArray[j])
swap(&dataArray[i],&dataArray[j]);
}
}
//打印排序后的数组
for(r=0;r<count;r++){
char cc;
cc = dataArray[r];
printf("%c",cc);
}
printf("\n");
system("pause");

}
//数值交换方法

void swap(char *a,char *b){
char temp;
temp = *a;
*a = *b;
*b = temp;

}