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<?php $str = "racecar"; $pal = ""; for($a=0; $a<strlen($str); $a++) { for($z=0; $z<strlen($str); $z++) $subs = substr($str, $a, $z); if( $subs == strrev($subs) and strlen($subs) > strlen($pal) ) { echo $a; $pal = $subs; } } echo $pal;
Finding entry points
Branch analysis from position: 0
1 jumps found. (Code = 42) Position 1 = 29
Branch analysis from position: 29
2 jumps found. (Code = 44) Position 1 = 32, Position 2 = 4
Branch analysis from position: 32
1 jumps found. (Code = 62) Position 1 = -2
Branch analysis from position: 4
1 jumps found. (Code = 42) Position 1 = 13
Branch analysis from position: 13
2 jumps found. (Code = 44) Position 1 = 16, Position 2 = 6
Branch analysis from position: 16
2 jumps found. (Code = 46) Position 1 = 21, Position 2 = 25
Branch analysis from position: 21
2 jumps found. (Code = 43) Position 1 = 26, Position 2 = 28
Branch analysis from position: 26
2 jumps found. (Code = 44) Position 1 = 32, Position 2 = 4
Branch analysis from position: 32
Branch analysis from position: 4
Branch analysis from position: 28
Branch analysis from position: 25
Branch analysis from position: 6
2 jumps found. (Code = 44) Position 1 = 16, Position 2 = 6
Branch analysis from position: 16
Branch analysis from position: 6
filename:       /in/38Nr4
function name:  (null)
number of ops:  34
compiled vars:  !0 = $str, !1 = $pal, !2 = $a, !3 = $z, !4 = $subs
line      #* E I O op                           fetch          ext  return  operands
-------------------------------------------------------------------------------------
    3     0  E >   ASSIGN                                                   !0, 'racecar'
    4     1        ASSIGN                                                   !1, ''
    6     2        ASSIGN                                                   !2, 0
          3      > JMP                                                      ->29
    9     4    >   ASSIGN                                                   !3, 0
          5      > JMP                                                      ->13
   10     6    >   INIT_FCALL                                               'substr'
          7        SEND_VAR                                                 !0
          8        SEND_VAR                                                 !2
          9        SEND_VAR                                                 !3
         10        DO_ICALL                                         $9      
         11        ASSIGN                                                   !4, $9
    9    12        PRE_INC                                                  !3
         13    >   STRLEN                                           ~12     !0
         14        IS_SMALLER                                               !3, ~12
         15      > JMPNZ                                                    ~13, ->6
   11    16    >   INIT_FCALL                                               'strrev'
         17        SEND_VAR                                                 !4
         18        DO_ICALL                                         $14     
         19        IS_EQUAL                                         ~15     !4, $14
         20      > JMPZ_EX                                          ~15     ~15, ->25
         21    >   STRLEN                                           ~16     !4
         22        STRLEN                                           ~17     !1
         23        IS_SMALLER                                       ~18     ~17, ~16
         24        BOOL                                             ~15     ~18
         25    > > JMPZ                                                     ~15, ->28
   12    26    >   ECHO                                                     !2
   13    27        ASSIGN                                                   !1, !4
    6    28    >   PRE_INC                                                  !2
         29    >   STRLEN                                           ~21     !0
         30        IS_SMALLER                                               !2, ~21
         31      > JMPNZ                                                    ~22, ->4
   18    32    >   ECHO                                                     !1
         33      > RETURN                                                   1

Generated using Vulcan Logic Dumper, using php 8.0.0


preferences:
159.9 ms | 1392 KiB | 17 Q