C Program to replace all lowercase vowels into uppercase in a string
Here is the C program to convert lowercase characters into uppercase and vice-versa.
#include<stdio.h>
#include<conio.h>
void main()
{ char str[200];
int i=0;
clrscr();
printf(“Enter a String:”);
gets(str);
printf(“Actual string:”);
puts(str);
for(i=0;str[i]!=’\0′;i++)
{ if(str[i]>=’A’ && str[i]<=’Z’)
{ str[i]=str[i]+32;
}
else
{ str[i]=str[i]-32;
}
}
printf(“Converted String:%s”,str);
getch();
}
Output
Logic of program
- The characters in lowercase can be converted into uppercase by using the logic of ASCII value.
- The ASCII value of lower characters(a-z) is 97-122 respectively and uppercase character(A-Z) is 65-90 respectively.
- So here it is clearly seen the difference in ASCII values of lowercase and uppercase characters is 32.
- So if the 32 is subtracted from the ASCII value of lowercase character than it can be converted into uppercase character and vice-versa.
- The loop used i.e for loop which will go to every single character of the string starting from i=0 to the null character(‘\0’).
- If-else is used for making a condition that if the character in a string is lowercase than it will follow the condition written in it and will convert it to uppercase and vice-versa.
