I am trying to verify all elements of an array[1..199] if there are negative elements. This code doesn't verify first element of the array. I am obliged to do this by recursive method.
I tried to do a separate condition, but this didn't worked. I firstly made it with for and then changed to recursive method.
Var a:array[1..100] of integer;n:integer;
Function E(n:integer):boolean;
Begin
if n=0 then E:=False
else if a[n]<0 then E:=True
else E:=E(n-1);
End;
Begin
readln(n);
for i:=1 to n do
readln(a[i]);
writeln('Are there negative numbers in array? ',E(n));
readln();
End;
I expect the output true if there are any negative elements or false if there not.
I am not a Pascal expert but I think you are looking for something like this:
program Hello;
var
arrayWithNegatives : array[1..10] of integer = (-1,20,30,40,50,60,71,80,90,91);
arrayWithPositives : array[1..10] of integer = (0,20,30,40,50,60,71,80,90,91);
emptyArray : array of integer;
Function HasNegativeNumbers(a: array of integer; n:integer):boolean;
Begin
if n < 0 then HasNegativeNumbers := False
else if a[n] < 0 then HasNegativeNumbers := True
else HasNegativeNumbers := HasNegativeNumbers(a, n - 1);
End;
begin
writeln (HasNegativeNumbers(arrayWithNegatives, length(arrayWithNegatives) - 1));
writeln (HasNegativeNumbers(arrayWithPositives, length(arrayWithPositives) - 1));
writeln (HasNegativeNumbers(emptyArray, length(emptyArray) - 1))
end.
Related
I'm learning algorithms and I'm trying to make an algorithm that extracts numbers lets say n in [1..100] from a string. Hopefully I get an easier algorithm.
I tried the following :
procedure ReadQuery(var t : tab); // t is an array of Integer.
var
x,v,e : Integer;
inputs : String;
begin
//readln(inputs);
inputs:='1 2 3';
j:= 1;
// make sure that there is one space between two integers
repeat
x:= pos(' ', inputs); // position of the space
delete(inputs, x, 1)
until (x = 0);
x:= pos(' ', inputs); // position of the space
while x <> 0 do
begin
x:= pos(' ', inputs); //(1) '1_2_3' (2) '2_3'
val(copy(inputs, 1, x-1), v, e); // v = value | e = error pos
t[j]:=v;
delete(inputs, 1, x); //(1) '2_3' (2) '3'
j:=j+1; //(1) j = 2 (2) j = 3
//writeln(v);
end;
//j:=j+1; // <--- The mistake were simply here.
val(inputs, v, e);
t[j]:=v;
//writeln(v);
end;
I get this result ( resolved ) :
1
2
0
3
expected :
1
2
3
PS : I'm not very advanced, so excuse me for reducing you to basics.
Thanks for everyone who is trying to share knowledge.
Your code is rather inefficient and it also doesn't work for strings containing numbers in general.
A standard and performant approach would be like this:
type
TIntArr = array of Integer;
function GetNumbers(const S: string): TIntArr;
const
AllocStep = 1024;
Digits = ['0'..'9'];
var
i: Integer;
InNumber: Boolean;
NumStartPos: Integer;
NumCount: Integer;
procedure Add(Value: Integer);
begin
if NumCount = Length(Result) then
SetLength(Result, Length(Result) + AllocStep);
Result[NumCount] := Value;
Inc(NumCount);
end;
begin
InNumber := False;
NumCount := 0;
for i := 1 to S.Length do
if not InNumber then
begin
if S[i] in Digits then
begin
NumStartPos := i;
InNumber := True;
end;
end
else
begin
if not (S[i] in Digits) then
begin
Add(StrToInt(Copy(S, NumStartPos, i - NumStartPos)));
InNumber := False;
end;
end;
if InNumber then
Add(StrToInt(Copy(S, NumStartPos)));
SetLength(Result, NumCount);
end;
This code is intentionally written in a somewhat old-fashioned Pascal way. If you are using a modern version of Delphi, you wouldn't write it like this. (Instead, you'd use a TList<Integer> and make a few other adjustments.)
Try with the following inputs:
521 cats, 432 dogs, and 1487 rabbits
1 2 3 4 5000 star 6000
alpha1beta2gamma3delta
a1024b2048cdef32
a1b2c3
32h50s
5020
012 123!
horses
(empty string)
Make sure you fully understand the algorithm! Run it on paper a few times, line by line.
I got this error when trying to compile.
left side cannot be assign to, ./number 21,22 in pastebin
here is my code
Program urut;
Uses Wincrt;
Const N = 5;
data: Array [1..N] Of Integer = (2,4,5,3,1);
Var
j,k,temp : Integer;
Begin
Clrscr;
Writeln ('Data sebelum diurutkan');
For j:=1 To N Do
Begin
Writeln('data[' ,j, ']= ',data [j]);
End;
For j:=1 To N-1 Do
Begin
For k :=N Downto j+1 Do
Begin
If data[k] < data[k-1] Then
Begin
temp := data[k];
data[k] := data[k-1]; //left side cannot be assigned to
data[k-1] := temp; //left side cannot be assigned to
End;
End;
End;
Writeln;
Writeln ('Data setelah diurutkan ');
For j:=1 To N Do
Begin
Writeln ('data[' ,j, '] = ',data[j]);
End;
Writeln;
End.
sorry for uncorrectly pattern post
, thank you so much.
Like tom Tom Brunberg says, my array is const, it can't be changed. Therefore I need to remove that const.
So it should be
data: Array [1..5] Of Integer = (value);
without const, and put it under var with another variable
I need an algorithm to print all possible sums of a number (partitions).
For example: for 5 I want to print:
1+1+1+1+1
1+1+1+2
1+1+3
1+2+2
1+4
2+3
5
I am writing my code in Pascal. So far I have this:
Program Partition;
Var
pole :Array [0..100] of integer;
n :integer;
{functions and procedures}
function Minimum(a, b :integer): integer;
Begin
if (a > b) then Minimum := b
else Minimum := a;
End;
procedure Rozloz(cislo, i :integer);
Var
j, soucet :integer;
Begin
soucet := 0;
if (cislo = 0) then
begin
for j := i - 1 downto 1 do
begin
soucet := soucet + pole[j];
if (soucet <> n) then
Write(pole[j], '+')
else Write(pole[j]);
end;
soucet := 0;
Writeln()
end
else
begin
for j := 1 to Minimum(cislo, pole[i - 1]) do
begin
pole[i] := j;
Rozloz(cislo - j, i + 1);
end;
end;
End;
{functions and procedures}
{Main program}
Begin
Read(n);
pole[0] := 101;
Rozloz(n, 1);
Readln;
End.
It works good but instead of output I want I get this:
1+1+1+1+1
2+1+1+1
2+2+1
3+1+1
3+2
4+1
5
I can't figure out how to print it in right way. Thank you for help
EDIT: changing for j:=i-1 downto 1 to for j:=1 to i-1 solves one problem. But my output is still this: (1+1+1+1+1) (2+1+1+1) (2+2+1) (3+1+1) (3+2) (4+1) (5) but it should be: (1+1+1+1+1) (1+1+1+2) (1+1+3) (1+2+2) (1+4) (2+3) (5) Main problem is with the 5th and the 6th element. They should be in the opposite order.
I won't attempt Pascal, but here is pseudocode for a solution that prints things in the order that you want.
procedure print_partition(partition);
print "("
print partition.join("+")
print ") "
procedure finish_and_print_all_partitions(partition, i, n):
for j in (i..(n/2)):
partition.append(j)
finish_and_print_all_partitions(partition, j, n-j)
partition.pop()
partition.append(n)
print_partition(partition)
partition.pop()
procedure print_all_partitions(n):
finish_and_print_all_partitions([], 1, n)
I need a code to go from decimal to binary numbers, but my program shows them invert, example: needs to show 1011000 but it brings out 0001101.
+ I cant use massives and array in this program.
var
x,y,i:longint;
BEGIN
readln(y);
repeat
x:= y mod 2;
y:= y div 2;
write(x);
until y = 0;
END.
I think you can use recursion function. For example:
procedure dec2bin(y)
BEGIN
x := y mod 2;
y := y mod 2;
if y > 1 then
dec2bin(y)
end
write(x)
END
BEGIN
readln(y);
dec2bin(y)
END.
I'm not sure in correct syntax because I working with Pascal long time ago. But I think you can understand my idea and make this.
This should answer what you are looking for
function decimalToBinary(a:LongInt):String;
var d:Integer;
str:String;
Begin
str:='';
while a>0 do begin
d:=a mod 2;
str:=concat(IntToStr(d),str);
a:=a div 2;
end;
decimalToBinary:=str;
End;
This is my code. It works!
program convert;
var
number : integer;
procedure dec2bin(x : integer);
begin
// general case
if (x > 1) then dec2bin(x div 2);
// to print the result
if (x mod 2 = 0) then write('0')
else write('1');
end;
begin
write('Decimal: '); readln(number);
write('Binary : ');
dec2bin(number);
end.
I have a project where the program must accept 10 words and display the words in descending order (alphabetical order from Z-A)
using bubble sorting.
Here's what I know so far:
Program sample;
uses crt;
TYPE
no._list=ARRAY(1...10)OF REAL;
CONST
no.:no._list=(20.00,50.50.35.70....);
VAR
x:INTEGER;
small:REAL;
BEGIN clrscr:
small:=no.(1);
FOR x:=2 TO 10 DO
IF small>number(x);
writeln('Smallest value in the array of no.s is',small:7:2);
END
I really don't know how to do this though and could use some help.
Here's a video by Alister Christie on Bubble sort describing the principle :
http://codegearguru.com/index.php?option=com_content&task=view&id=64&Itemid=1
The algorithm in Pascal can be found # http://delphi.wikia.com/wiki/Bubble_sort
function BubbleSort( list: TStringList ): TStringList;
var
i, j: Integer;
temp: string;
begin
// bubble sort
for i := 0 to list.Count - 1 do begin
for j := 0 to ( list.Count - 1 ) - i do begin
// Condition to handle i=0 & j = 9. j+1 tries to access x[10] which
// is not there in zero based array
if ( j + 1 = list.Count ) then
continue;
if ( list.Strings[j] > list.Strings[j+1] ) then begin
temp := list.Strings[j];
list.Strings[j] := list.Strings[j+1];
list.Strings[j+1] := temp;
end; // endif
end; // endwhile
end; // endwhile
Result := list;
end;