10018 - Reverse and Add

[Articuno]

Well hi abid. Your code is alright. But you have done a little mistake. In your code you forgot a simple thing.
Have a close look:

Code: Select all

Removed

Set the flag to 0.
You will get Ac.
Wish you good luck.

[abid_iut]

thankx Articuno
U r a great helper
pls continue helping me like this

[lucasbls1]

I don't know what's wrong with my code,
please somebody help me..

#include <stdio.h>
#include <string.h>
#include <stdlib.h>

void str_reverse(char* str)
{
char ch;
int i, j;

for(i = 0, j = strlen(str) - 1; i < j; ++i, --j)
{
ch = str;
str = str[j];
str[j] = ch;
}
}

main()
{
int qtde;
int i=0;
unsigned long num_original, num_invertido, num_resultado, teste;
char str[15];
char str_copia[15];
char* str_inutil[15];
char res_backup[1];
int cont;
scanf("%d\n", & qtde);

for(i=0; i< qtde; i++)
{
cont=1;


scanf("%s\n", str);

while(1)
{

str_copia[0] = '\0';
res_backup[0] = '\0';

strcpy(str_copia, str);

str_reverse(str);

num_original = strtoul(str_copia, str_inutil, 10);
num_invertido = strtoul(str, str_inutil, 10);

num_resultado = num_original + num_invertido;

char* res;
res = (char*) malloc(sizeof(char)*11);
res[0] = '\0';
str_inutil[0] = '\0';

sprintf(res, "%lu", num_resultado);


strcpy(res_backup, res);
str_reverse(res);

if(strcmp(res_backup, res)==0)
{

printf("%d %lu", cont, num_resultado);
if(i!=qtde-1)
printf("\n");
break;
}
else
{

cont++;
str[0] = '\0';

strcpy(str, res_backup);

}



}



}

}

[sefakilic]

Read the problem description:

You might assume that all tests data on this problem:
- will have an answer ,
- will be computable with less than 1000 iterations (additions),
- will yield a palindrome that is not greater than 4,294,967,295.

long is not enough for this problem. Use unsigned long, unsigned int or long long. The reason of the TLE of your code is most likely integer overflow.

Hello,

I got AC, but I am still wondering.

In problem description, it says that resulting palindrome <= 4,294,967,295.

So, it means that all numbers before the resulting palindrome is less than 4,294,967,295.
So, why unsigned int is not enough?

my compiler gcc is 4.2.4. and sizeof(unsigned int) is 4 byte. So 2^32 < 4,294,967,295.

[@mjad]

hi i am trying to solve it but it is TE.
help me, about it please..........

[sohel]

Use the search option at the top right corner to look for existing discussions related to your problem.
Don't create a new thread - make your post in an existing one!

[@mjad]

thanks to reply
finally i got AC

[Martuza_iu]

Why I get time limit exit? pls help me.

Code: Select all

#include<stdio.h>
int main()
{
    long long int nm,rm[10000]={0},i,c,rv,b,d,j,m;
	scanf("%ll",&m);
	for(j=0;j<m;j++)
	{
	scanf("%ll",&nm);
	d=-1;
	b=0;
	while(b!=rv)
	{
		d=d+1;
		b=nm;
	c=0;
	for(i=0;nm!=0;i++)
	{
	rm[i]=nm%10;
	nm=nm/10;
	c=c+1;
	}
	rv=0;
	for(i=0;i<c;i++)
		rv=rv*10+rm[i];
		nm=b+rv;
	}
		printf("%ll %ll\n",d,rv);
	}
	return 0;
}

[tanvirfromhell]

Why i got WA?

Code: Select all

#include<stdio.h>
#include<stdlib.h>

int main()
{
    int a,rs=0,r,i,fs,b,n,count;

    scanf("%d",&n);

    for(i=1;i<=n;i++)
    {
        scanf("%d",&a);

        rs=0;
        count=0;

        while(a!=0)
        {
            b=a;
            rs=0;

            while(a!=0)
                {
                    r=a%10;
                    rs=rs*10+r;
                    a=a/10;
                }

            fs=b+rs;
            a=fs;

            if( b == rs )
            break;
            count++;

        }
    printf("%d %d\n",count,rs);

    }
    return 0;
}

[aansu]

can someone tell me why this gets a WA?

Code: Select all

using namespace std;
#include<iostream>
#define LLU long long unsigned 
LLU rev(LLU x)
{
    LLU i=0;
    while (x!=0)
    {
          i=i*10+(x%10);
          x/=10;
    }
    return i;
}
bool ispalin(LLU x)
{
     int NO[20],i=0;
     while (x!=0)
     {
           NO[i++]=x%10;
           x/=10;
     }
     i--;
     for (int j=0;j<i;j++,i--)
         if(NO[i]!=NO[j]) return false;
     return true;
}   
int main()
{
    int cases,inp,cnt;
    cin>>cases;
    while (cases--)
    {
          cin>>inp;
          cnt=0;
          while (!ispalin(inp))
          {
                inp=inp+rev(inp);
                cnt++;
          }
          cout<<cnt<<" "<<inp<<endl;
    }
    return 0;
}

[Munna_csedu]

#include<stdio.h>
int count;
long long reverse(long long);
long long palindrome(long long n)
{
long long rev,p,m;
m=n;
rev=0;
while(n!=0)
{
p=n%10;
n=n/10;
rev=10*rev+p;
}
if(m==rev)
return rev;
else
return reverse(rev);


}
long long reverse(long long n)
{
long long rev,p,m;
m=n;
rev=0;
while(n!=0)
{
p=n%10;
n=n/10;
rev=10*rev+p;
}
count++;
return palindrome(rev+m);
}

int main()
{
long long k,t,n,pal;
scanf("%lld",&t);
for(k=1;k<=t;k++)
{
scanf("%lld",&n);
pal=palindrome(reverse(n));
printf("%d %lld\n",count,pal);
count=0;
}
return 0;
}


what is my problem??
i cant think anything
pls help meeeeeeeeeeee

[tzupengwang]

Can anyone help?
Thanks~

Code: Select all

Removed after AC

[brianfry713]

a is a long long int and should be printed with format code %lld

[tzupengwang]

Thanks a lot~ I got AC
What a silly mistake I've made

[FAR14]

#include<stdio.h>
#include <conio.h>
int counter=1;
void palindrome(int a)
{
int flag=0;
int reverse=0;
int digit,temp;
int local=a;
int rev = 0;

while(a !=0)
{
digit=a%10;
reverse=reverse*10+digit;
a=a/10;
}
printf("reversed number=%d ",reverse);
int t=reverse+local;

printf("after addition=%d \n",t);

temp = t;

while( temp != 0 )
{
rev = rev * 10;
rev= rev+ temp%10;
temp = temp/10;
}

if ( t == rev )
{
printf("%d (iteration needed) %d(palindrome number).\n",counter, t);

}
else
{
counter++;
palindrome(t);

}


}

void main()
{

int input;
printf("Enter the number: ");
scanf("%d",&input);
palindrome(input);
getch();
}