Accept a name and print the initial of the name.

Read a string from user using gets() function. Now travel the whole string and pick out the first character of every word and convert it into upper case and concat a '.' character. Now pick out the last word an concat it to the result.

int main()
{
	char str[30],res[30],i,w,k=0;
	//READ A STRING
	printf("Enter A String: ");
	gets(str);
	for(i=0;str[i]!='\0';i++)
	{
		if((str[i]>=65 && str[i]<=90) ||(str[i]>=97 && str[i]<=122))
		{
			if(i==0 ||str[i-1]==' ')
			{
				w=i+1;
				if(str[i]>=97 && str[i]<=122)
				{
					str[i]=str[i]-32;
				}
				res[k++]=str[i];
				res[k++]='.';
			}
		}
	}
	k--;
	for(i=w;str[i]!='\0';i++)
	{
		if(str[i]>=65 && str[i]<=90)
		{
			res[k++]=str[i]+32;
		}
		else
		{
			res[k++]=str[i];
		}
	}
	res[k++]='.';
	res[k]='\0';
	//PRINT THE OUTPUT
	printf("Result : ");
	puts(res);
	return 0;
}

Enter A String: rabinDra natH tagore
Result : R.N.Tagore.