Program a menu driven program showing several operations on string.

Program
#include
#include
#include
void stringlen(char s1);
void stringcopy(char *s1);
void stringcon(char *s1);
void stringrev(char *s1);
void stringcompare(char *s1);
void wordcount(char *s1);
void lettercount(char *s1);
void main()
{
char s[40],x;
clrscr();
printf("\n Enter a string");
gets(s1);
printf("\n Enter 'a' for string length");
printf("\n Enter 'b' for string copy");
printf("\n Enter 'c' for string concatanation");
printf("\n Enter 'd' for string rev");
printf("\n Enter 'e' for string compare");
printf("\n Enter 'f' for word count within a string");
printf("\n Enter 'g' for letter count within a string\n");
scanf("%2c",&x);
switch(x)
{
case 'a':
stringlen(s1);
break;
case 'b':
stringcopy(s1);
break;
case 'c':
stringcon(s1);
break;
case 'd':
stringrev(s1);
break;
case 'e':
stringcompare(s1);
break;
case 'f':
wordcount(s1);
break;
case 'g':
lettercount(s1);
break;
}
}
void stringlen(char *s1)
{
int n=0;i=0;
while(s[i]!=NULL)
{
n++;
i++;
}
printf("length of the string is:-\n%d",n);
getch();
}
void stringcopy(char *s1)
{
int i;
char s2[40];
for(i=0;s1[i]=!NULL;i++)
{
s2=s1[i];
}
s2[i]=NULL;
printf("NEW STRING IS;-\n%s",s2);
getch();
}
void stringconcatanation(char *s1)
{
int i,j;
char str[40];
printf("ENTER ANOTHER STRING:-\n");
fflush(stdin);
gets(str);
for(i=0;s1[i]!=NULL;i++);
for(j=0;s1[j]!=NULL;j++)
{
s1[i]=str[j];
i++;
s1[i]=NULL;
}
printf("NEW STRING IS;-\n%s",s1);
getch();
}
void stringrev(char *s1)
{
int i,c=0,l;
char s2[100];
l=strlen(s1);
for(i=l-1;i>=0;i--)
s2[c++]=s1[i];
printf("NEW STRING IS \n");
for(i=0;i
printf("%c",s2[i]);
getch();
}
void stringcompare(char *s1)
{
int i,flag=1;
char s2[40];
printf("ENTER ANOTHER STRING");
fflush(stdin);
gets(*s2);
for(i=0;s2[i]!=NULL;i+)
{
if(s1[i]!=s2[i])
{
printf("\n not equal");
flag=0;break;
}
}
if(flag==1)
printf("equal");
getch();
}