Wrong answer PALIN

[dharmjit]

the code for next palindrome is running successfully on my pc for all the test cases i had used whereas i am getting wrong answer on spoj.please tell the case where I am getting wrong answer
below is the code.

#include <cstdlib>
#include <iostream>
#include <string>
using namespace std;
string nine(string str,int i,int j)
{
       for(i;i<str.length();i++,j--)
                    {
                    if((str[i]=='9')&&(str[j]=='9'))
                        {
                         str[i]='0';
                         str[j]='0';
                          }
                    else 
                          break;
                      }
                          if(j==-1)
                          {
                                 str[i-1]='1';
                                 str='1'+str;
                          }
                          else
                          {
                         str[j]++;
                         str[i]++;}
                         return str;
                           }
bool ispalindrome(string str)
         {
         bool ispal=true;;
         int j=str.length()-1;
         for(int i=0;i<=j;i++,j--)
               {
               if(str[i]!=str[j])
                         {
                         ispal=false;
                         break;
                         }
                }
             return ispal;      
           }
int main()
       {
       int n;
        string s,t;
        bool ispalin;
        std::cin>>n;
        for(int p=0;p<=n;p++)
                        {
                        getline(cin,s);
                        t=s;
                        int n=s.length();
                        ispalin=ispalindrome(s);
                        if(n==1)
                        std::cout<<s;
                        else if(ispalin)
                                 {
                                   if((n%2)== 0)
                                               {
                                               if(s[(n/2)]=='9')
                                               {s=nine(s,(n/2),(n/2)-1);}
                                               else
                                                      {
                                                      s[(n/2)-1]++;
                                                      s[(n/2)]++; 
                                                        }              
                                                 }
                                   else
                                                 {
                                                 if(s[(n/2)]=='9')
                                                 {s=nine(s,n/2,n/2);}
                                                  else
                                                 s[(n/2)]=s[(n/2)]+1;
                                                  } 
                                        std::cout<<s;
                      }
   else
                     {
                    if((n%2)==0)
                            {
                            int j=((n/2)-1);
                             int i=(n/2);
                             for(i;i<n;i++,j--)
                                        {
                                       t[i]=t[j];
                                         }  
                                    if(s<t)
                                    std::cout<<t;  
                                    else  
                                                 {
                                                  t[(n/2)-1]++;
                                                  t[(n/2)]++;   
                                                  std::cout<<t;
                                                     }   
                               }
                 else
                              {
                              int i=(n/2)+1;
                                int j=(n/2)-1;
                              for(i;i<n;i++,j--)
                                          {
                                           t[i]=t[j];
                                          }
                                if(s<t)
                                std::cout<<t;
                                else
                                         {
                                          t[(n/2)]++;
                                           std::cout<<t;
                                         }
                  }
       }
        std::cout<<endl;
    }}

[leppyr64]

Please edit your post and use the code tags. Your code is very difficult to read as it is currently presented.

[dharmjit]

code editted have a look

[leppyr64]

Input:

10
1
2
3
4
5
6
7
8
9
10

[artdivin]

Hello, i am running all the tests correctly but i am getting WA.

Could anyone please help? Algorithm is pretty clear:

#include <iostream>
#include <vector>
#include <string>
#include <cstdlib>
#include <algorithm>
#include <stdio.h>
using namespace std;
bool isPalyndrome(string &numStr) {
	string reverseStr(numStr.length(), ' ');
	std::copy(numStr.begin(), numStr.end(), reverseStr.begin());
	std::reverse(reverseStr.begin(), reverseStr.end());
	return reverseStr.compare(numStr);
}
void insertNumber(string &numStr, int num, int eraseIdx) {
	char chr = num + '0';
	numStr.insert(eraseIdx, 1, chr);
	numStr.erase(eraseIdx + 1, 1);
}
void mirroredString(string &originalStr) {
	int idx = 0;
	int backIdx = originalStr.length() - 1;
    while (true) {
	originalStr[backIdx] = originalStr[idx];
	idx++;
	backIdx--;
	if (idx >= backIdx)
		break;
}
}
int main() {
	int lineCount = 0;
	vector<string> palyns;
	cin >> lineCount;
	for (int i = 0; i < lineCount; i++) {
		string numStr;
		cin >> numStr;
    	while (true) {

		char zeroChar = numStr.at(0);
		char lastChar = numStr.at(numStr.length() - 1);
		int zeroCharInt = 0;
		int lastCharInt = 0;
		sscanf(&zeroChar, "%d", &zeroCharInt);
		sscanf(&lastChar, "%1d", &lastCharInt);
		if (zeroCharInt <= lastCharInt) {
			int idx = numStr.length() / 2; // get the middle idx

			if (numStr.length() == 1)
				idx = 0;
			else
				if ((numStr.length() % 2) == 0)
					idx--;
			while (true) {

				if (idx < 0) {
					numStr.insert(0, 1, '1');
					mirroredString(numStr);
					break;
				}

				char chr = numStr.at(idx);
				int val = atoi(&chr);
				val++;

				if (val == 10) {
					insertNumber(numStr, 0, idx < 0 ? 0 : idx);
					idx--;
					continue;
				} else {
					insertNumber(numStr, val, idx < 0 ? 0 : idx);
					mirroredString(numStr);
					break;
				}
			}

		} else {
			mirroredString(numStr);
		}

		if (!isPalyndrome(numStr)) {
			palyns.push_back(numStr);
			break;
		}
		else
			continue;
	}
}

for (vector<string>::iterator it = palyns.begin(); it < palyns.end(); it++)
	cout << *it << "\n";

return 0;
}

[artdivin]

done test is 7957 - next palindrome is 7997, but my code gave me 8008

edit: hm. Tests are working perfectly - every single test i can find in web... Still WA

here is corrected code:

#include <iostream>
#include <vector>
#include <string>
#include <cstdlib>
#include <algorithm>
#include <stdio.h>
using namespace std;
bool isPalyndrome(string &numStr) {
	string reverseStr(numStr.length(), ' ');
	std::copy(numStr.begin(), numStr.end(), reverseStr.begin());
	std::reverse(reverseStr.begin(), reverseStr.end());
	return reverseStr.compare(numStr);
}
void insertNumber(string &numStr, int num, int eraseIdx) {
	char chr = num + '0';
	numStr.insert(eraseIdx, 1, chr);
	numStr.erase(eraseIdx + 1, 1);
}
void mirroredString(string &originalStr) {
	int idx = 0;
	int backIdx = originalStr.length() - 1;
    while (true) {
	originalStr[backIdx] = originalStr[idx];
	idx++;
	backIdx--;
	if (idx >= backIdx)
		break;
}
}
bool isLeftGreater(string &originalStr) {
    bool result = true;
int idx = 0;
int backIdx = originalStr.length() - 1;
while (true) {

	char zeroChar = originalStr.at(idx);
	char lastChar = originalStr.at(backIdx);
	int zeroCharInt = 0;
	int lastCharInt = 0;
	sscanf(&zeroChar, "%d", &zeroCharInt);
	sscanf(&lastChar, "%1d", &lastCharInt);

	if (idx != 0) {
		if (zeroCharInt > lastCharInt) {
			result = true;
		} else
			if ((zeroCharInt < lastCharInt) && result) {
				result = false;
			}
	} else
		if (zeroCharInt < lastCharInt)
			result = false;

	idx++;
	backIdx--;
	if (idx >= backIdx)
		break;
}

return result;
}
int main() {
	int lineCount = 0;
	vector<string> palyns;
	cin >> lineCount;
	for (int i = 0; i < lineCount; i++) {
		string numStr;
		cin >> numStr;
    	bool isNew = true;

	while (true) {
		if (isNew) {
			if (!isPalyndrome(numStr)) {

			} else {
				if (isLeftGreater(numStr)) {
					mirroredString(numStr);
					if (!isPalyndrome(numStr)) {
						palyns.push_back(numStr);
						break;
					}
				}
			}

			isNew = false;
		}


		int idx = numStr.length() / 2; // get the middle idx

		if (numStr.length() == 1)
			idx = 0;
		else
			if ((numStr.length() % 2) == 0)
				idx--;
		while (true) {

			if (idx < 0) {
				numStr.insert(0, 1, '1');
				break;
			}

			char chr = numStr.at(idx);
			int val = atoi(&chr);
			val++;

			if (val == 10) {
				insertNumber(numStr, 0, idx < 0 ? 0 : idx);
				idx--;
				continue;
			} else {
				insertNumber(numStr, val, idx < 0 ? 0 : idx);
				break;
			}
		}

		mirroredString(numStr);

		if (!isPalyndrome(numStr)) {
			palyns.push_back(numStr);
			break;
		}
		else
			continue;
	}
}

for (vector<string>::iterator it = palyns.begin(); it < palyns.end(); it++)
	cout << *it << "\n";

return 0;
}

please, HELP!!!! It's driving me crazy.

numbers for testing:

10
1
2
3
4
5
6
7
8
9
10

---

16
3
9
53936
53236
67775
99
999
6339
875111
6997
7957
9798
2107
3109
456156
2133

---

[artdivin]

HOORAY !!!!!!!!!!!!!!! YEAH! YEAH YEAH!!!! YEEEAAAAHHH!!!

YEAH!

Did it!
There was something wrong with insertNumber() method (insert + erase on std::string is buggy!) - modified it with simple numStr[index] = character - worked juuust fiiine!

[leppyr64]

Congratulations!

[shubham_depp1_sof]

This is my code please tell me what is wrong in this....PlzzzzzzzzzzzzzzzzzzzzzZZZZ??????
I am getting all answers correct...

#include<stdio.h>
#include<string.h>
int main()
{
	int t,count;
	scanf("%d\n",&t);
	for(count=0;count<t;count++)
	{
		int i=0,length=0,flag=0,check=0,z;
		char number[1000001],num[1000001];
		gets(number);	
		length=strlen(number);
		for(i=0;i<length;i++)
		{
			if(number[i]=='9')
				flag=1;
			else
			{
				flag=0;
				break;
			}
		}
		if(flag==1)
		{
			printf("1");
			for(i=1;i<length;i++)
				printf("0");
			printf("1\n");
		}
		else
		{
			z=((length-length%2)/2)+length%2;
			for(i=0;i<z;i++)
			{
				num[i]=number[i];
				num[length-i-1]=number[i];
			}
			for(i=0;i<length;i++)
			{
				if((num[i]-'0')>(number[i]-'0'))
				{
					check=1;
				}
				else if((num[i]-'0')<(number[i]-'0'))
				{
					check=0;
					break;
				}
				else
				{
					check=0;
				}
			}
			if(check==0)
			{
				for(i=z-1;i>=0;i--)
				{
					if(num[i]=='9')
					{
						num[i]='0';
					}
					else
					{
						num[i]++;
						num[length-1-i]=num[i];
						break;
					}
				}
			}
			for(i=0;i<length;i++)
			printf("%c",num[i]);
			printf("\n");
		}
	}
	return 0;
}

[kalujny_sof]

MWHAAAHAHAHAHAHA

MWHAHAHAHAHAHAHAHAHAHAAA

(more madman laugh)

NEVER. NEVER use

std::cin.sync_with_stdio(false);

in SPOJ.com problems, it will eventually **** you in the ass instead of speeding your code up.

[leppyr64]

Not necessarily, just make sure you don't mix iostream and cstdio input methods if you do

[vijetha_35]

I got the right answer! but when I submit the following code, it says wrong answer. please help me out and lemme know where I have gone wrong.

#include <iostream>
#include<stdio.h>
using namespace std;
short int rever(int n)
{
         int temp = n,reverse=0;
       while( temp != 0 )
     {
      reverse = reverse * 10;
      reverse = reverse + temp%10;
      temp = temp/10;
     } 
   if ( n == reverse )
   {
       printf("%d\n",n);
       return 1;
   }
  return -1;
}
int main()
{
    int t,n,temp;
    short int r=0;
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d",&n);
        while(n++)
        {
            r=rever(n);
            if(r==1)break;
        }
    }
  return 0;
}

[leppyr64]

What is the largest value that will fit in an int? What is the largest possible value in the input?

[sstwilight]

ideone.com/BQYCYw
the above is link to my C code.. I'm getting a TLE error when running it on spoj.. I assume the reason being the complexity of my code..I'm a beginner.. plz assist me..

[leppyr64]

I'm feeling like a broken record lately.

What's the largest number that will fit inside long long? What is the largest possible value in the input?