The Fibonacci Sequence

[XML] [Smart Pascal] [JavaScript] [Python] [output]

See Dr Ron Knott's Fibonacci page for the relevance of the sequence in nature. Fibonacci number 0 is 0 and Fibonacci number 1 is 1. Thereafter, each term of the sequence is equal to the sum of the preceding two terms.

We used the Blockly Playground to generate Python code from the same blocks.

The blocks

The blocks

XML Code of Blocks

<xml xmlns="http://www.w3.org/1999/xhtml">
  <block type="variables_set" id="QN{xq__QQA[W?%aGW/KQ" x="29" y="67">
    <field name="VAR">intLastButOne</field>
    <value name="VALUE">
      <block type="math_number" id="fFV2{V2jwcXqmLichv4U">
        <field name="NUM">0</field>
      </block>
    </value>
    <next>
      <block type="variables_set" id="]9Bod/Rj7$2rW]}a$~l*">
        <field name="VAR">intLast</field>
        <value name="VALUE">
          <block type="math_number" id="DTUY,~cRxpLk88J--@em">
            <field name="NUM">1</field>
          </block>
        </value>
        <next>
          <block type="text_print" id="mC0G3r,O|[u7goZT}ho-">
            <value name="TEXT">
              <shadow type="text" id="LP|wr8*/(sbt?Ru8R9Pd">
                <field name="TEXT">abc</field>
              </shadow>
              <block type="text_join" id="6U$v:sam4dA3jpgA)cEa">
                <mutation items="2"></mutation>
                <value name="ADD0">
                  <block type="text" id="djF6H6;^=fz~8;ACbkH(">
                    <field name="TEXT">Fibonacci number 0: </field>
                  </block>
                </value>
                <value name="ADD1">
                  <block type="variables_get" id="czCZ6)1!8y!}^XK.R38!">
                    <field name="VAR">intLastButOne</field>
                  </block>
                </value>
              </block>
            </value>
            <next>
              <block type="text_print" id="GYAnApz6pTTv*x?Pc{o8">
                <value name="TEXT">
                  <shadow type="text" id="LP|wr8*/(sbt?Ru8R9Pd">
                    <field name="TEXT">abc</field>
                  </shadow>
                  <block type="text_join" id="YsS$9K!~%yQDT2N_}tb,">
                    <mutation items="2"></mutation>
                    <value name="ADD0">
                      <block type="text" id="}ngQTWjVNyp#t5Z^%pp!">
                        <field name="TEXT">Fibonacci number 1: </field>
                      </block>
                    </value>
                    <value name="ADD1">
                      <block type="variables_get" id="IXKxZ4iw]/^y?NTjgctD">
                        <field name="VAR">intLast</field>
                      </block>
                    </value>
                  </block>
                </value>
                <next>
                  <block type="controls_for" id="~}n.$JeC60O=K:!)7V]Z">
                    <field name="VAR">i</field>
                    <value name="FROM">
                      <shadow type="math_number" id="DO@:#+=3,n7RbZRdLA6C">
                        <field name="NUM">1</field>
                      </shadow>
                    </value>
                    <value name="TO">
                      <shadow type="math_number" id="+)|IpKzV+wVO)OPHty?R">
                        <field name="NUM">19</field>
                      </shadow>
                    </value>
                    <value name="BY">
                      <shadow type="math_number" id="KhP:2YKpu$r,o$rnZe9N">
                        <field name="NUM">1</field>
                      </shadow>
                    </value>
                    <statement name="DO">
                      <block type="variables_set" id="FLsG0$:l445CUaiwwN5=">
                        <field name="VAR">intCurrent</field>
                        <value name="VALUE">
                          <block type="math_arithmetic" id="sk5)}%ezXM_}8V9nGf@e">
                            <field name="OP">ADD</field>
                            <value name="A">
                              <shadow type="math_number" id="d:)qV4vuNFFC6;vn@{,5">
                                <field name="NUM">1</field>
                              </shadow>
                              <block type="variables_get" id="LFM[2RrGBq:-CJR}~gBa">
                                <field name="VAR">intLastButOne</field>
                              </block>
                            </value>
                            <value name="B">
                              <shadow type="math_number" id="rg]?;UT~hj5nxt:wHhl|">
                                <field name="NUM">1</field>
                              </shadow>
                              <block type="variables_get" id="VA:nitAL-d-[!#HXndRx">
                                <field name="VAR">intLast</field>
                              </block>
                            </value>
                          </block>
                        </value>
                        <next>
                          <block type="text_print" id="k(H?S7X50#UT$PEzV;p9">
                            <value name="TEXT">
                              <shadow type="text" id="LP|wr8*/(sbt?Ru8R9Pd">
                                <field name="TEXT">abc</field>
                              </shadow>
                              <block type="text_join" id="JihEkAQK:btZGb5HG=#;">
                                <mutation items="4"></mutation>
                                <value name="ADD0">
                                  <block type="text" id="Hf@Fc7akVLkX*$;!FOxt">
                                    <field name="TEXT">Fibonacci number </field>
                                  </block>
                                </value>
                                <value name="ADD1">
                                  <block type="math_arithmetic" id="P$^1f:}3l|40EPXh0VZh">
                                    <field name="OP">ADD</field>
                                    <value name="A">
                                      <shadow type="math_number" id=")8$5JxTq^iAoAg[8`G`r">
                                        <field name="NUM">1</field>
                                      </shadow>
                                      <block type="variables_get" id="HKRF0471+@q2Wm/{Zd/{">
                                        <field name="VAR">i</field>
                                      </block>
                                    </value>
                                    <value name="B">
                                      <shadow type="math_number" id="z0YQ6JiIxiAQQ)~|Jy_:">
                                        <field name="NUM">1</field>
                                      </shadow>
                                    </value>
                                  </block>
                                </value>
                                <value name="ADD2">
                                  <block type="text" id="2,!9Hqv]bFW!n}H#np;C">
                                    <field name="TEXT">: </field>
                                  </block>
                                </value>
                                <value name="ADD3">
                                  <block type="variables_get" id="uy]6GvNyRs2k?sRk12|Q">
                                    <field name="VAR">intCurrent</field>
                                  </block>
                                </value>
                              </block>
                            </value>
                            <next>
                              <block type="variables_set" id="=tq`h%WJ{FI,|X1P+f`Z">
                                <field name="VAR">intLastButOne</field>
                                <value name="VALUE">
                                  <block type="variables_get" id="/k*^rRhKHoLFmPWx|6UU">
                                    <field name="VAR">intLast</field>
                                  </block>
                                </value>
                                <next>
                                  <block type="variables_set" id="z|ZEV;T{;8nU0UUd[xSd">
                                    <field name="VAR">intLast</field>
                                    <value name="VALUE">
                                      <block type="variables_get" id="w5(X~wYYW?vKmWtNA;d#">
                                        <field name="VAR">intCurrent</field>
                                      </block>
                                    </value>
                                  </block>
                                </next>
                              </block>
                            </next>
                          </block>
                        </next>
                      </block>
                    </statement>
                  </block>
                </next>
              </block>
            </next>
          </block>
        </next>
      </block>
    </next>
  </block>
</xml>

Generated Smart Pascal Code

var intCurrent: Integer;
var intLast: Integer;
var intLastButOne: Integer;


function Str(v: Variant) : string;
begin
  asm
    if (@v === 0) {
      @Result = '0';
    }
    else if (@v === '') {
      @Result = '';
    }
    else if (isNaN(@v)) {
      @Result = @v;
    }
    else {
      @Result = (@v).toString();
    }
  end;
end;



intLastButOne := 0;
intLast := 1;
Console.writeln(Str('Fibonacci number 0: ') + Str(intLastButOne));
Console.writeln(Str('Fibonacci number 1: ') + Str(intLast));
for var i := 1 to 19 do
begin
  intCurrent := intLastButOne + intLast;
  Console.writeln(StrJoin([Str('Fibonacci number '), Str(i + 1), Str(': '), Str(intCurrent)],''));
  intLastButOne := intLast;
  intLast := intCurrent;
end;

Generated JavaScript

var intCurrent, intLast, intLastButOne, i;


intLastButOne = 0;
intLast = 1;
window.alert(String('Fibonacci number 0: ') + String(intLastButOne));
window.alert(String('Fibonacci number 1: ') + String(intLast));
for (i = 1; i <= 19; i++) {
  intCurrent = intLastButOne + intLast;
  window.alert(['Fibonacci number ',i + 1,': ',intCurrent].join(''));
  intLastButOne = intLast;
  intLast = intCurrent;
}

Generated Python Code

intCurrent = None
intLast = None
intLastButOne = None
i = None


intLastButOne = 0
intLast = 1
print(str('Fibonacci number 0: ') + str(intLastButOne))
print(str('Fibonacci number 1: ') + str(intLast))
for i in range(1, 20):
  intCurrent = intLastButOne + intLast
  print(''.join([str(x) for x in ['Fibonacci number ', i + 1, ': ', intCurrent]]))
  intLastButOne = intLast
  intLast = intCurrent

Copy of Output

Fibonacci number 0: 0
Fibonacci number 1: 1
Fibonacci number 2: 1
Fibonacci number 3: 2
Fibonacci number 4: 3
Fibonacci number 5: 5
Fibonacci number 6: 8
Fibonacci number 7: 13
Fibonacci number 8: 21
Fibonacci number 9: 34
Fibonacci number 10: 55
Fibonacci number 11: 89
Fibonacci number 12: 144
Fibonacci number 13: 233
Fibonacci number 14: 377
Fibonacci number 15: 610
Fibonacci number 16: 987
Fibonacci number 17: 1597
Fibonacci number 18: 2584
Fibonacci number 19: 4181
Fibonacci number 20: 6765
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Programming - a skill for life!

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