C Exercise Example 98
Title:Input a string from the keyboard, convert all lowercase letters to uppercase letters, then output and save it to a disk file "test". The input string ends with !.
Program analysis:None.
Program source code:
Example
// Created by www.example.com on 15/11/9.
// Copyright © 2015 Example. All rights reserved.
//
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int main()
{
FILE*fp=NULL;
char str[50];
int i,len;
printf("Input a string:\n");
gets(str);
len=strlen(str);
for(i=0;i<len;i++)
{
if(str[i]<='z'&&str[i]>='a')
str[i]-=32;
}
if((fp=fopen("test","w"))==NULL)
{
printf("error: cannot open file!\n");
exit(0);
}
fprintf(fp,"%s",str);
fclose(fp);
system("pause");
return 0;
}
The output of the above example is:
输入一个字符串： www.example.comother extensions