Thread: Printing Length of Input and the Limited Input

So instead of a while statement, would it be better to use If?
Or would it be more efficient to change the while loop? Thanks!

Code:

if (c != '\n'){
        ++possiblemax;
}

Code:

while((c=getchar()) != '\n'){
        ++possiblemax;
}

Originally Posted by dnguyen1022

So instead of a while statement, would it be better to use If?
Or would it be more efficient to change the while loop? Thanks!

Code:

if (c != '\n'){
        ++possiblemax;
}

Code:

while((c=getchar()) != '\n'){
        ++possiblemax;
}

You might want to change your loop -- currently it stops at EOF, instead of \n.

So I changed my code a little bit...I don't think it ever reaches the part where c is equal to a new line within the while loop though. How would I fix this?

Code:

#include <stdio.h>
#define MAXLINE 10

int getLine(char line[], int maxline);
void copy(char to[], char from[]);

//prints longest input line
main(){
	int len; //current line length
	int max; //maximum length seen so far
	int possiblemax; //possible maximum length
	int realmax; //the real maximum length
	int c; //the char
    char line[MAXLINE]; //current input line
	char longest[MAXLINE]; //longest line saved here
	
    max = possiblemax = realmax = 0;

	while ((len = getline(line, MAXLINE)) > 0)
		//checks to see if array ends with a new line
		if (line[len - 1] != '\n'){

			//while c is not end of file
			while ((c = getchar()) != '\n'){
				//if c is not equal to a new line
				if (c != '\n'){
					//if c is not a new line add one to possible max
					++possiblemax;		 
				}

				//else if is equal to a new line
				else if (c == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }
            }
        }
                                            
		if (len > max){
			max = len;
			copy(longest, line);
		}

		if (max > 0){ //there was a line
			printf("length:%d", realmax);
			putchar('\n');
			printf("%s", longest);
		}
		return 0;
}

//read a line into s, return length
int getline(char s[], int lim){
	int c, i;

	for(i = 0; i < lim-1 && (c = getchar()) != EOF && c != '\n'; ++i)
		s[i] = c;
	if(c == '\n'){
		s[i] = c;
		++i;
	}
	s[i] = '\0';
	return i;
}

//copy from into to: assume to is big enough
void copy(char to[], char from[]){
	int i;

	i = 0;
	while ((to[i] = from[i]) != '\0')
		++i;
}

So now I thought about it again and tried a different approach. My program now doesn't freeze anymore. However it doesn't return anything back...just tells me to press any key to continue.

Code:

#include <stdio.h>
#define MAXLINE 10

int getLine(char line[], int maxline);
void copy(char to[], char from[]);

//prints longest input line
main(){
	int len; //current line length
	int max; //maximum length seen so far
	int possiblemax; //possible maximum length
	int realmax; //the real maximum length
	int c; //the char
    char line[MAXLINE]; //current input line
	char longest[MAXLINE]; //longest line saved here
	
    max = possiblemax = realmax = 0;

	while ((len = getline(line, MAXLINE)) > 0)
		//checks to see if array ends with a new line
		if (line[len - 1] != '\n'){

				//if c is not equal to a new line
				if ((c = getchar()) != '\n'){
					//if c is not a new line add one to possible max
					++possiblemax;		 
				}

				//else if is equal to a new line
				else if ((c = getchar()) == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }
            }
                                            
		if (len > max){
			max = len;
			copy(longest, line);
		}

		if (max > 0){ //there was a line
			printf("length:%d", realmax + MAXLINE);
			putchar('\n');
			printf("%s", longest);
		}
		return 0;
}

//read a line into s, return length
int getline(char s[], int lim){
	int c, i;

	for(i = 0; i < lim-1 && (c = getchar()) != EOF && c != '\n'; ++i)
		s[i] = c;
	if(c == '\n'){
		s[i] = c;
		++i;
	}
	s[i] = '\0';
	return i;
}

//copy from into to: assume to is big enough
void copy(char to[], char from[]){
	int i;

	i = 0;
	while ((to[i] = from[i]) != '\0')
		++i;
}

bump..I still need help...

You do realize the code you've posted doesn't compile? (There is no definition of the symbol "getline" when the function is called, because your prototype is for getLine.)

Okay..I fixed it..it didn't seem to be having any problems compiling in Microsoft Visual C++ though. I think I know why it did not compile in c++ bloodshed though.

Code:

#include <stdio.h>
#define MAXLINE 10

int getline(char line[], int maxline);
void copy(char to[], char from[]);

//prints longest input line
main(){
	int len; //current line length
	int max; //maximum length seen so far
	int possiblemax; //possible maximum length
	int realmax; //the real maximum length
	int c; //the char
    char line[MAXLINE]; //current input line
	char longest[MAXLINE]; //longest line saved here
	
    max = possiblemax = realmax = 0;

	while ((len = getline(line, MAXLINE)) > 0)
		
		if (len > max){
			max = len;
			copy(longest, line);
		}
		
		//checks to see if array ends with a new line
		if (line[len - 1] != '\n'){

				//if c is not equal to a new line
				if ((c = getchar()) != '\n'){
					//if c is not a new line add one to possible max
					++possiblemax;		 
				}

				//else if is equal to a new line
				else if ((c = getchar()) == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }
            }
                                            
		
		realmax = realmax + max;

		if (max > 0){ //there was a line
			printf("length:&#37;d", realmax);
			putchar('\n');
			printf("%s", longest);
		}
		return 0;
}

//read a line into s, return length
int getline(char s[], int lim){
	int c, i;

	for(i = 0; i < lim-1 && (c = getchar()) != EOF && c != '\n'; ++i)
		s[i] = c;
	if(c == '\n'){
		s[i] = c;
		++i;
	}
	s[i] = '\0';
	return i;
}

//copy from into to: assume to is big enough
void copy(char to[], char from[]){
	int i;

	i = 0;
	while ((to[i] = from[i]) != '\0')
		++i;
}

Here is the correct code without the spelling mistake. However it still does the same thing..gives me a length only up to 9.

Code:

else if ((c = getchar()) == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }

You realize this will only happen when there are two enter-keys in a row?

I am not sure what you mean by two enter keys in a row...can you explain it please? As in press enter twice? I realized I had to do that, but I do not see why my coding would produce such a result.

Originally Posted by tabstop

Code:

while(c != '\n'){
	++possiblemax;
}

Good luck getting that loop to stop. That's assuming you decide on the name of the function getL/line, since your program doesn't compile as is. And is the point of this c thing in main to throw away the rest of the line?

Didn't you tell me that loop would never stop? Also I removed that getchar() from my else if, but it seems like I still have to press enter twice.

Code:

#include <stdio.h>
#define MAXLINE 10

int getline(char line[], int maxline);
void copy(char to[], char from[]);

//prints longest input line
main(){
	int len; //current line length
	int max; //maximum length seen so far
	int possiblemax; //possible maximum length
	int realmax; //the real maximum length
	int c; //the char
    char line[MAXLINE]; //current input line
	char longest[MAXLINE]; //longest line saved here
	
    max = possiblemax = realmax = 0;

	while ((len = getline(line, MAXLINE)) > 0)
		
		if (len > max){
			max = len;
			copy(longest, line);
		}
		
		//checks to see if array ends with a new line
		if (line[len - 1] != '\n'){
				
				(c = getchar());

				//while c is not equal to a new line
				while (c != '\n'){
					//while c is not a new line add one to possiblemax
					++possiblemax;
				}

				//if is equal to a new line
				if (c  == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }
            }
                                            
		
		realmax = realmax + max;

		if (max > 0){ //there was a line
			printf("length:%d", realmax);
			putchar('\n');
			printf("%s", longest);
		}
		return 0;
}

//read a line into s, return length
int getline(char s[], int lim){
	int c, i;

	for(i = 0; i < lim-1 && (c = getchar()) != EOF && c != '\n'; ++i)
		s[i] = c;
	if(c == '\n'){
		s[i] = c;
		++i;
	}
	s[i] = '\0';
	return i;
}

//copy from into to: assume to is big enough
void copy(char to[], char from[]){
	int i;

	i = 0;
	while ((to[i] = from[i]) != '\0')
		++i;
}

It sure does look like it is infinitely going on with this code though. I also moved the (c = getchar()); to the outside of the if and else statements.

The while and the getchar need to be together, as the only thing that can make your while loop stop is the getchar! You need to change c inside the loop, not ten lines away.

Oh I get what you are saying..However now my program does nothing at all, no matter how many "enter-keys" I put in. Assuming my while loop works, I think it may have to do with when my code actually reaches a new line.

Code:

#include <stdio.h>
#define MAXLINE 10

int getline(char line[], int maxline);
void copy(char to[], char from[]);

//prints longest input line
main(){
	int len; //current line length
	int max; //maximum length seen so far
	int possiblemax; //possible maximum length
	int realmax; //the real maximum length
	int c; //the char
    char line[MAXLINE]; //current input line
	char longest[MAXLINE]; //longest line saved here
	
    max = possiblemax = realmax = 0;

	while ((len = getline(line, MAXLINE)) > 0)
		
		if (len > max){
			max = len;
			copy(longest, line);
		}
		
		//checks to see if array ends with a new line
		if (line[len - 1] != '\n'){

				//while c is not equal to a new line
				while ((c = getchar()) != '\n'){
					//while c is not a new line add one to possible max
					++possiblemax;
				}

				//if is equal to a new line
				if (c  == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }
            }
                                            
		
		realmax = realmax + max;

		if (max > 0){ //there was a line
			printf("length:&#37;d", realmax);
			putchar('\n');
			printf("%s", longest);
		}
		return 0;
}

//read a line into s, return length
int getline(char s[], int lim){
	int c, i;

	for(i = 0; i < lim-1 && (c = getchar()) != EOF && c != '\n'; ++i)
		s[i] = c;
	if(c == '\n'){
		s[i] = c;
		++i;
	}
	s[i] = '\0';
	return i;
}

//copy from into to: assume to is big enough
void copy(char to[], char from[]){
	int i;

	i = 0;
	while ((to[i] = from[i]) != '\0')
		++i;
}

Also I must say thank you for your patience with me! =]

Your indentation is lying to you, perhaps. Do you want to be able to type in more than one line?

Code:

while ((len = getline(line, MAXLINE)) > 0)
		{
		if (len > max){
			max = len;
			copy(longest, line);
		}
		
		//checks to see if array ends with a new line
		if (line[len - 1] != '\n'){

				//while c is not equal to a new line
				while ((c = getchar()) != '\n'){
					//while c is not a new line add one to possible max
					++possiblemax;
				}

				//if is equal to a new line
				if (c  == '\n'){
					//if possiblemax is greater than real max
					//set realmax to possiblemax
					//reset possible max
					if (possiblemax > realmax){
                                realmax = possiblemax;
                                possiblemax = 0;
                }

				//otherwise reset possiblemax
					else possiblemax = 0;
                }
            }
                               }             
		
		realmax = realmax + max;

		if (max > 0){ //there was a line
			printf("length:%d", realmax);
			putchar('\n');
			printf("%s", longest);
		}
		return 0;
}

Maybe add the pair of braces, so that the while loop sees more than just the reading-in part.