713 - Adding Reversed Numbers

[Joseph Kurniawan]

Wow!!!
This really scares me. So my stat of solved prob isn't true for sure? There can be probs that's acc for mere dumb luck???

[Ivor]

to be sure you would need to test your program with any possible input. And that could take GIGABYTES of input files. And some programs you can't test with all cases at all -> you'll run out of living time! If you got your solution accepted, it means that it is correct with high probability (99.9%? depends on how good is the input file).

Ivor

[Joseph Kurniawan]

Yeah, I think you're right. After all it's just a brain exercise, nothing to lose!!!

[ravingavin]

It keeps on telling me that I have a compile error, and I have no idea what the deal is.

I'm using Visual C++, and it's giving me no errors. I know little about compilers and libraries.

I've got a feeling it's to do with me using the cstring library. If someone could notify me of what to change then I would really appreciate it.


Thanks for you help!!

GCS

Code: Select all

#include <iostream>
#include <cstring>
#include <cmath>

using namespace std;

int main(){

	char x[30];
	char y[30];
	int final[30];
	char *xcopy, *ycopy;
	int N, length1, length2, xtemp, ytemp, remember,temp, answer, modulus;

	cin >> N;

	int i=0;

	while(i < N){

		cin >> x >> y;

		length1 = strlen(x);

		int p = length1-1;
		
		xcopy = new char[length1];

		for(int t=0; t < length1; t++){
			xcopy[t] = x[p];

			p--;
		} 
		
		length2 = strlen(y);

		p = length2-1;

		ycopy = new char[length2];

		for(t=0; t < length2; t++){
			ycopy[t] = y[p];

			p--;
		} 

		xtemp = atoi(xcopy);

		ytemp = atoi(ycopy);

		xtemp += ytemp;

		t=1;

		while(pow(10,t)/xtemp < 1)
			t++;

		temp= pow(10,t-1);

		if(xtemp != temp*10){

			remember= t;

			while(t != 0){
			
				temp= pow(10,t-1);
			
				modulus = (xtemp % temp);
			
				answer= ((xtemp - modulus) / temp);

				final[t-1] = answer;

				xtemp = modulus;

				t--;
			}

			for(int b=0; b < remember; b++)
				cout << final[b];
		}
		else{
			cout << "1" << endl;
		}


		cout << endl;

		delete [] xcopy;
		delete [] ycopy;

		i++;

	}



	return 0;

}

[jpfarias]

These are the errors I've got when I compiled your code on the gnu g++ compiler with -ansi and -Wall flags:

Code: Select all

teste.cpp: In function `int main()':
teste.cpp:41: name lookup of `t' changed for new ISO `for' scoping
teste.cpp:29:   using obsolete binding at `t'
teste.cpp:55: call of overloaded `pow(int, int&)' is ambiguous
/usr/include/bits/mathcalls.h:154: candidates are: double pow(double, double)
/usr/include/c++/3.2.3/cmath:427:                 long double std::pow(long 
   double, int)
/usr/include/c++/3.2.3/cmath:423:                 float std::pow(float, int)
/usr/include/c++/3.2.3/cmath:419:                 double std::pow(double, int)
/usr/include/c++/3.2.3/cmath:410:                 long double std::pow(long 
   double, long double)
/usr/include/c++/3.2.3/cmath:401:                 float std::pow(float, float)
teste.cpp:58: call of overloaded `pow(int, int)' is ambiguous
/usr/include/bits/mathcalls.h:154: candidates are: double pow(double, double)
/usr/include/c++/3.2.3/cmath:427:                 long double std::pow(long 
   double, int)
/usr/include/c++/3.2.3/cmath:423:                 float std::pow(float, int)
/usr/include/c++/3.2.3/cmath:419:                 double std::pow(double, int)
/usr/include/c++/3.2.3/cmath:410:                 long double std::pow(long 
   double, long double)
/usr/include/c++/3.2.3/cmath:401:                 float std::pow(float, float)
teste.cpp:66: call of overloaded `pow(int, int)' is ambiguous
/usr/include/bits/mathcalls.h:154: candidates are: double pow(double, double)
/usr/include/c++/3.2.3/cmath:427:                 long double std::pow(long 
   double, int)
/usr/include/c++/3.2.3/cmath:423:                 float std::pow(float, int)
/usr/include/c++/3.2.3/cmath:419:                 double std::pow(double, int)
/usr/include/c++/3.2.3/cmath:410:                 long double std::pow(long 
   double, long double)
/usr/include/c++/3.2.3/cmath:401:                 float std::pow(float, float)

Maybe MSVC++ is not ansi compatible. Ansi is the standard used in Valladolid online judge. Look in MSVC++ options if there is a ansi compatible setting you can set and try compiling again.... Anyway, you can get Cygwin or MingW which are the gnu compilers ported to windows.

JP!

[ravingavin]

Thanks....I found the error! The error was that I kept on using 'i' in the for loops after using it the first time in a for loop. It obviously destroys the variable in memory once the for loop ends.

Thanks for your help!!

[ravingavin]

Thanks for your help again!!! Well, I thought that I had everything correct, but I've submitted it and apparently there is something wrong with my code.

Could someone give me some test cases in which my code is incorrect. I know that i'm really close, so it's probaly a minor error.

Thanks once again!

GCS

Code: Select all

#include <iostream>
#include <string>
#include <cmath>

using namespace std;

int main(){

	char x[30];
	char y[30];
	char *xcopy, *ycopy;
	int N, length1, length2, xtemp, ytemp, remember,temp, answer, modulus, *final;

	cin >> N;

	int i=0;

	while(i < N){

		cin >> x >> y;

		length1 = strlen(x);

		int p = length1-1;
		
		xcopy = new char[length1];

		for(int t=0; t < length1; t++){
			xcopy[t] = x[p];

			p--;
		} 
		
		length2 = strlen(y);

		p = length2-1;

		ycopy = new char[length2];

		for(int g=0; g < length2; g++){
			ycopy[g] = y[p];

			p--;
		} 

		xtemp = atoi(xcopy);

		ytemp = atoi(ycopy);

		xtemp += ytemp;

		int f=1;

		while(pow(10,f)/xtemp < 1)
			f++;

		temp= pow(10,f-1);

		final = new int[f];

		if(xtemp != temp*10){

			remember= f;

			while(f != 0){
			
				temp= pow(10,f-1);
			
				modulus = (xtemp % temp);
			
				answer= ((xtemp - modulus) / temp);

				final[f-1] = answer;
				
				xtemp = modulus;
				
					f--;
				
			}


			int w=0;
			
			for(int b=0; b < remember; b++){
				if(w==0 && final[b] == 0)
					continue;
				
				else if(w==0 && final[b] != 0)
					w++;

					cout << final[b];
			}

			if(w==0)
				cout << "0";
			
		}
		else{
			cout << "1" << endl;
		}


		cout << endl;

		delete [] xcopy;
		delete [] ycopy;
		delete [] final;

		i++;

	}
		


	return 0;

}

[jpfarias]

I've found one error:

[cpp]
else{
cout << "1" << endl;
}


cout << endl;
[/cpp]

This will produce 2 endl, which is wrong....

Don't know if there are other errors....

JP.

[ravingavin]

Thanks...I didn't notice that error. I've corrected the error by it's still giving me WA.

GCS

[ravingavin]

Could somebody perhaps give me some good input test data, so I can see where my program is going wrong? I cannot find the problem. It keeps on giving me WA.

Thanks for your help!!

GCS

[lky]

any critical data in this problems.....i tryed loads of them ....but still dunno why WA

here is my code:
program q713;
uses wincrt;
var a:array[1..300]of integer;
n,i,j,k,u,v:integer;
s,s1,s2,t1,t2:string;
check:boolean;
begin
readln(n);
for i:=1 to n do
begin
check:=false;
readln(s);
for j:=1 to 300 do
a[j]:=0;
for j:=1 to length(s) do
if s[j]=' '
then k:=j;
s1:=copy(s,1,k-1);
s2:=copy(s,k+1,length(s)-k);
for j:=1 to length(s1) do
t1[j]:=s1[length(s1)+1-j];
for j:=1 to length(s2) do
t2[j]:=s1[length(s2)+1-j];
for j:=1 to length(s2) do
a[j]:=a[j]+ord(s2[j])-48;
for j:=1 to length(s1) do
a[j]:=a[j]+ord(s1[j])-48;

if length(s2)>length(s1)
then begin
for j:=1 to length(s2) do
if a[j]>=10
then begin
a[j+1]:=a[j+1]+1;
a[j]:=a[j]-10
end;
end
else begin
for j:=1 to length(s1) do
if a[j]>=10
then begin
a[j+1]:=a[j+1]+1;
a[j]:=a[j]-10
end;
end;
for j:=300 downto 1 do
if (a[j]<>0)and(check=false)
then begin
u:=j;
check:=true
end;
check:=false;
for j:=1 to 300 do
if (a[j]<>0)and(check=false)
then begin
v:=j;
check:=true
end;
for j:=v to u do
write(a[j]);
writeln
end
end.

[Morning]

[java]
import java.io.*;
import java.util.*;

class Main
{
static String reverse(String str) //utility function to reverse the string
{
char [] chr = new char [str.length()];
for(int loop = str.length() - 1;loop >= 0;loop--)
{
chr[str.length() - 1 - loop] = str.charAt(loop);
}
return (new String(chr));
}
static String ReadLn (int maxLg) // utility function to read from stdin
{
byte lin[] = new byte [maxLg];
int lg = 0, car = -1;
while (lg < maxLg)
{
car = System.in.read();
if ((car < 0) || (car == '\n')) break;
lin [lg++] += car;
}
return (new String (lin, 0, lg));
}

public static void main (String args[]) // entry point from OS
{
Main myWork = new Main(); // create a dinamic instance
myWork.Begin(); // the true entry point
}

void Begin()
{
String input,revC;
StringTokenizer idata;
int times,a,b,c;
input = Main.ReadLn(255);
idata = new StringTokenizer (input);
times = Integer.parseInt (idata.nextToken());
while (times > 0)
{
times--; //count the times
input = Main.ReadLn(255);
input = new String(reverse(input));
idata = new StringTokenizer (input);
a = Integer.parseInt (idata.nextToken());
b = Integer.parseInt (idata.nextToken());
c = a + b;
revC = new String(reverse(Integer.toString(c)));
idata = new StringTokenizer (revC);
c = Integer.parseInt (idata.nextToken());
System.out.println(c);
}
}
}
[/java]

[Morning]

[java]
import java.io.*;
import java.util.*;

class Main
{
static String reverse(String str) //utility function to reverse the string
{
char [] chr = new char [str.length()];
for(int loop = str.length() - 1;loop >= 0;loop--)
{
chr[str.length() - 1 - loop] = str.charAt(loop);
}
return (new String(chr));
}
static String ReadLn (int maxLg) // utility function to read from stdin
{
byte lin[] = new byte [maxLg];
int lg = 0, car = -1;
while (lg < maxLg)
{
car = System.in.read();
if ((car < 0) || (car == '\n')) break;
lin [lg++] += car;
}
return (new String (lin, 0, lg));
}

public static void main (String args[]) // entry point from OS
{
Main myWork = new Main(); // create a dinamic instance
myWork.Begin(); // the true entry point
}

void Begin()
{
String input,revC;
StringTokenizer idata;
int times,a,b,c;
input = Main.ReadLn(255);
idata = new StringTokenizer (input);
times = Integer.parseInt (idata.nextToken());
while (times > 0)
{
times--; //count the times
input = Main.ReadLn(255);
input = new String(reverse(input));
idata = new StringTokenizer (input);
a = Integer.parseInt (idata.nextToken());
b = Integer.parseInt (idata.nextToken());
c = a + b;
revC = new String(reverse(Integer.toString(c)));
idata = new StringTokenizer (revC);
c = Integer.parseInt (idata.nextToken());
System.out.println(c);
}
}
}[/java]

[sohel]

After rejudging I got WA too.

This problem looks straight forward and I don't know why I keep getting Wrong Answer.

I don't usually post my code(AC or WA) in this board but as the code is very short I couldn't refrain myself from doing so.

here is my code:
[cpp]
#include<stdio.h>
#include<string.h>

void srev(char val[])
{
int l,i;
char t;
l = strlen(val) - 1;
for(i=0;i<l;i++)
{
t = val;
val = val[l];
val[l] = t;
l--;
}
}
int main()
{
int in, j, i,k;
int t;
long x,y,sum;
char str1[10000], str2[10000];
scanf("%d",&t);
while(t--)
{
scanf("%ld %ld",&x, &y);
sprintf(str1,"%ld",x);
sprintf(str2,"%ld",y);
srev(str1);
srev(str2);
sscanf(str1,"%ld",&x);
sscanf(str2,"%ld",&y);
sum = x + y;
sprintf(str1,"%ld",sum);
srev(str1);
sscanf(str1,"%ld",&x);
printf("%ld\n",x);
}


return 0;
}
[/cpp]

Can someone tell me why this simple program gets WA.
Thanx.

[Morning]

our algorithm seems likely:)