Cleanup/speedup: $(()) changed to (()). Remove ${} when not needed

Boost speed in some cases

Author: einarjon

02.sh

@@ -1,8 +1,8 @@
 #! /usr/bin/env bash
 ans=0
 IFS=$'-:\ \n'
-while read m M b c; do x=${c//[^$b]}; [[ ${#x} -ge $m && ${#x} -le $M ]] && ans=$((ans+1)); done < ${1:-2.txt}
+while read m M b c; do x=${c//[^$b]}; [[ ${#x} -ge $m && ${#x} -le $M ]] && ((++ans)); done < ${1:-2.txt}
 echo "2A: $ans"
 ans=0
-while read m M b c; do x=${c:$((m-1)):1}; y=${c:$((M-1)):1}; [[ $x != $y ]] && [[ $b == $x || $b == $y ]] && ans=$((ans+1)); done < ${1:-2.txt}
+while read m M b c; do x=${c:m-1:1}; y=${c:M-1:1}; [[ $x != $y ]] && [[ $b == $x || $b == $y ]] && ((++ans)); done < ${1:-2.txt}
 echo "2B: $ans"

03.sh

@@ -1,8 +1,8 @@
 #! /usr/bin/env bash
 A=($(< ${1:-3.txt})); l=${#A[0]}; k=0; j=3; total=1; x=""
-for i in ${A[@]}; do x+=${i:k:1}; k=$(((k+j)%l)); done; x=${x//\.}
+for i in ${A[@]}; do x+=${i:k:1}; ((k=(k+j)%l)); done; x=${x//\.}
 echo "3A: ${#x}"
 idx2=$(seq 0 2 $((${#A[@]}-1)))
-for j in 1 3 5 7; do x=""; k=0; for i in ${A[@]}; do x+=${i:k:1}; k=$(((k+j)%l)); done; x=${x//\.}; total+="*${#x}"; done
-for j in 1; do x=""; k=0; for i in $idx2; do x+=${A[i]:k:1}; k=$(((k+j)%l)); done ; x=${x//\.}; total+="*${#x}"; done
+for j in 1 3 5 7; do x=""; k=0; for i in ${A[@]}; do x+=${i:k:1}; ((k=(k+j)%l)); done; x=${x//\.}; total+="*${#x}"; done
+for j in 1; do x=""; k=0; for i in $idx2; do x+=${A[i]:k:1}; ((k=(k+j)%l)); done ; x=${x//\.}; total+="*${#x}"; done
 echo "3B: ${total:2} = $((total))"

04.sh

@@ -1,6 +1,6 @@
 #! /usr/bin/env bash
-X='epEhbiH'; x=$X; ans=""
-IFS=$'\r\n\ '
+X='epEhbiH'; x=$X; ans=0
+IFS=$' \n'
 A=($(sed s/^$/XXX/ ${1:-4.txt}))
 for i in "${A[@]}" XXX; do
     case $i in
@@ -12,11 +12,11 @@ for i in "${A[@]}" XXX; do
         iyr:*) x=${x/i};;
         hgt:*) x=${x/H};;
         cid:*) : ;;
-        XXX) [ -z "$x" ] && ans+=1; x=$X;;
+        XXX) [ -z "$x" ] && ((ans+=1)); x=$X;;
     esac
 done
-echo "4A: ${#ans}"
-x=$X; ans=""
+echo "4A: ${ans}"
+x=$X; ans=0
 for i in "${A[@]}" XXX; do
     k=${i/*:}
     case $i in
@@ -29,7 +29,7 @@ for i in "${A[@]}" XXX; do
         hgt:[0-9][0-9]in) [[ ${k:0:2} -ge 59 && ${k:0:2} -le 76 ]] && x=${x/H};;
         hgt:1[0-9][0-9]cm) [[ ${k:0:3} -ge 150 && ${k:0:3} -le 193 ]] && x=${x/H};;
         cid:*) : ;;
-        XXX) [ -z "$x" ] && ans+=1; x=$X;;
+        XXX) [ -z "$x" ] && ((ans+=1)); x=$X;;
     esac
 done
-echo "4B: ${#ans}"
+echo "4B: ${ans}"

06.sh

@@ -1,19 +1,20 @@
 #! /usr/bin/env bash
-X=abcdefghijklmnopqrstuvwxyz; x=$X; j=-; a=0
+X=abcdefghijklmnopqrstuvwxyz; x=$X; a=0
 A=($(sed s/^$/X/ ${1:-6.txt}))
+A+=(X)
 while read -n1 i; do
-    [ "$i" = X ] && a=$((a+26-${#x})) && x=$X
+    [ "$i" = X ] && { ((a+=26-${#x})); x=$X; }
     x=${x/$i}
-done < <(echo ${A[*]} X)
+done <<< "${A[*]}"
 echo "6A: $a";
 
 x=""; a=0
-for line in "${A[@]}" X; do
-  if [[ "$line" = X ]]; then a=$((a+${#x})); x=X;
+for line in "${A[@]}"; do
+  if [[ "$line" = X ]]; then ((a+=${#x})); x=X;
   elif [ "$x" = X ]; then x=$line;
   else
       y=""; while read -n1 i; do [[ ${x/$i} != ${x} ]] && y+="$i"; done <<< $line
-    #  y="";for ((i=0;i<${#line};i++ )); do [[ ${x/${line:$i:1}} != ${x} ]] && y+="${line:$i:1}"; done
+    #  y="";for ((i=0;i<${#line};i++ )); do [[ ${x/${line:i:1}} != ${x} ]] && y+="${line:i:1}"; done
       x=$y;
   fi
 done

07.sh

@@ -7,14 +7,14 @@ BAGS=("${NEW[@]}")
 while [ ${#FOUND[@]} != 0 ]; do
     NEW=($(grep -F "${FOUND[*]}" $input | grep -v -F "${BAGS[*]}" | sort -u))
     BAGS+=("${NEW[@]}")
-	FOUND=("${NEW[@]// bag*}")
+    FOUND=("${NEW[@]// bag*}")
 done
 echo "7A: ${#BAGS[@]}"
 r(){
     local A=() a=${1// *} b=0 c=0
     A=($(grep ^${1:2} $input | grep -o "[0-9] [a-z]* [a-z]*"))
-    for i in "${A[@]}"; do c=$(r $i); b=$((b+c)); done
-    echo $(($a+$a*$b))
+    for i in "${A[@]}"; do c=$(r $i); ((b+=c)); done
+    echo $((a+a*b))
 }
 total=$(r "1 shiny gold")
 echo "7B: $((total-1))" # minus 1 shiny gold bag

08.sh

@@ -8,9 +8,9 @@ solve8() {
         x=${A[i]}; y=${x/* }; A[i]+=DONE
         case "$x" in
             *DONE) return 1;;
-            acc*) acc=$((acc+($y))); i=$((i+1));;
-            jmp*) i=$((i+($y)));;
-            nop*) i=$((i+1)) ;;
+            acc*) ((acc+=y,++i));;
+            jmp*) ((i+=y));;
+            nop*) ((++i));;
             *) echo "ERROR $i: $x"; return 1;;
         esac
         [[ $i -ge ${#A[@]} ]] && return 0
@@ -27,4 +27,3 @@ for k in ${!A[@]}; do
     A=("${B[@]}")
 done
 [[ $i -ge ${#A[@]} ]] && echo "8B: $acc"
-

09.sh

@@ -15,8 +15,8 @@ done
 
 k=0; j=0; sum=${A[j++]}
 while [ $sum != ${A[i]} ]; do
-    if [[ $sum -lt ${A[i]} ]]; then   sum=$((sum+A[j++]))
-    elif [[ $sum -gt ${A[i]} ]]; then sum=$((sum-A[k++]))
+    if   [[ $sum -lt ${A[i]} ]]; then ((sum+=A[j++]))
+    elif [[ $sum -gt ${A[i]} ]]; then ((sum-=A[k++]))
     fi
     [[ $j -ge $i ]] && echo NOT FOUND && break
 done

10.sh

@@ -1,8 +1,8 @@
 #! /usr/bin/env bash
 A=($(sort -n ${1:-10.txt}))
-DIFF=("" "" "" "1") # add 3 for the built-in
-j=0; for i in "${A[@]}"; do DIFF[$((i-j))]+=1;j=$i; done
-echo "10A: ${#DIFF[1]}*${#DIFF[3]}=$((${#DIFF[1]}*${#DIFF[3]}))"
+DIFF=(0 0 0 1) # add 3 for the built-in
+j=0; for i in "${A[@]}"; do ((DIFF[i-j]+=1));j=$i; done
+echo "10A: ${DIFF[1]}*${DIFF[3]}=$((${DIFF[1]}*${DIFF[3]}))"
 B=; j=0; for i in "${A[@]}"; do B+=$((i-j)); j=$i; done; B+=3;
 C=(${B//3/ }) # only works because there are nothing but 1s and 3s
 D=(0 1 2 4 7)

11.sh

@@ -6,21 +6,21 @@ while [ ${#change} != 0 ]; do
     change=(); l=
     for i in $I; do
         for j in $J; do
-            x=${B[i]:$j:1};
+            x=${B[i]:j:1}
             if [[ "$x" == "L" || "$x" == "X" ]]; then
-                s="${B[i-1]:$((j-1)):3}${B[i]:$((j-1)):1}${B[i]:$((j+1)):1}${B[i+1]:$((j-1)):3}";
-                s=${s//[L.]/}
-                if [[ ${#s} == 0 ]]; then x=X; elif [[ ${#s} -ge 4 ]]; then x=L; fi;  k=$((k+1))
-            fi;
-            l+=$x;
+                s="${B[i-1]:j-1:3}${B[i]:j-1:3}${B[i+1]:j-1:3}"
+                s=${s//[L.]}; s=${s/$x}
+                if [[ ${#s} == 0 ]]; then x=X; elif [[ ${#s} -ge 4 ]]; then x=L; fi
+            fi
+            l+=$x
         done
         [ "${B[i]}" != .$l. ] && change+=($((i-1)) $i $((i+1)))
         C[i]=.$l.; l=
     done
     B=("${C[@]}")
     I=$(printf "%s\n" ${change[@]} |sort -u)
-    [ $((++round)) = 1 ] && B=("${C[@]//X/x}")
-    #[ $((round%10)) = 0 ] && echo "$round: $((${#change[@]}/3))"
+    ((++round==1)) && B=("${C[@]//X/x}")
+    #((round%10)) || echo "$round: $((${#change[@]}/3))"
 done
 ans="${B[*]}"; ans=${ans//[ L.]}
 echo "11A: ${#ans}"
@@ -29,29 +29,29 @@ echo "11A: ${#ans}"
 B=(L${A//?/L}L); for i in "${A[@]}"; do B+=(L${i}L); done; B+=($B)
 J=$(seq ${#A}); I=$(seq ${#A[@]}); change=1; round=0
 while [ ${#change} != 0 ]; do
-    change=""; C=($B); l="";
+    change=""; C=($B); l=""
     for i in $I; do
         for j in $J; do
-            x=${B[i]:$j:1};
+            x=${B[i]:j:1}
             [[ "$x" != "L" && "$x" != "X" ]] && l+=$x && continue
             r=${B[i]:j+1}; r=${r//.}; R=${B[i]:0:j}; R=${R//.}
             s=${R: -1}${r:0:1}
-            k=1; d=${B[i-k]:j-k:1}; while [ "$d" = '.' ]; do k=$((k+1)); d=${B[i-k]:j-k:1}; done; s+=$d
-            k=1; d=${B[i-k]:j:1};   while [ "$d" = '.' ]; do k=$((k+1)); d=${B[i-k]:j:1};   done; s+=$d
-            k=1; d=${B[i-k]:j+k:1}; while [ "$d" = '.' ]; do k=$((k+1)); d=${B[i-k]:j+k:1}; done; s+=$d
-            k=1; d=${B[i+k]:j-k:1}; while [ "$d" = '.' ]; do k=$((k+1)); d=${B[i+k]:j-k:1}; done; s+=$d
-            k=1; d=${B[i+k]:j:1};   while [ "$d" = '.' ]; do k=$((k+1)); d=${B[i+k]:j:1};   done; s+=$d
-            k=1; d=${B[i+k]:j+k:1}; while [ "$d" = '.' ]; do k=$((k+1)); d=${B[i+k]:j+k:1}; done; s+=$d
+            k=1; d=${B[i-k]:j-k:1}; while [ "$d" = '.' ]; do ((++k)); d=${B[i-k]:j-k:1}; done; s+=$d
+            k=1; d=${B[i-k]:j:1};   while [ "$d" = '.' ]; do ((++k)); d=${B[i-k]:j:1};   done; s+=$d
+            k=1; d=${B[i-k]:j+k:1}; while [ "$d" = '.' ]; do ((++k)); d=${B[i-k]:j+k:1}; done; s+=$d
+            k=1; d=${B[i+k]:j-k:1}; while [ "$d" = '.' ]; do ((++k)); d=${B[i+k]:j-k:1}; done; s+=$d
+            k=1; d=${B[i+k]:j:1};   while [ "$d" = '.' ]; do ((++k)); d=${B[i+k]:j:1};   done; s+=$d
+            k=1; d=${B[i+k]:j+k:1}; while [ "$d" = '.' ]; do ((++k)); d=${B[i+k]:j+k:1}; done; s+=$d
             #[[ ${#s} == 8 ]] || echo "ERROR: ($s) $k = $i, $j"
             s=${s//L}
             if [[ ${#s} == 0 ]]; then l+=X; elif [[ ${#s} -ge 5 ]]; then l+=L; else l+=$x; fi
         done
         [ ${B[i]} != L${l}L ] && change+=1
         C+=(L${l}L); l=
     done
-    C+=($B); B=("${C[@]}");
-    [ $((++round)) = 1 ] && B=("${C[@]//X/x}")
-    #[ $((round%10)) = 0 ] && echo "$round: ${#change}"
+    C+=($B); B=("${C[@]}")
+    ((++round==1)) && B=("${C[@]//X/x}")
+    #((round%10)) || echo "$round: ${#change}"
 done
 sum="${B[*]}"; sum=${sum//[ L.]}
 echo "11B: ${#sum}"

12.sh

@@ -3,29 +3,31 @@ A=($(< ${1:-12.txt}))
 H=1; X=0; Y=0; D=(N E S W)
 for i in "${A[@]}"; do
     i=${i/F/${D[H]}}
+    n=${i:1}
     case $i in
-        N*) Y+=+${i:1};;
-        S*) Y+=-${i:1};;
-        E*) X+=+${i:1};;
-        W*) X+=-${i:1};;
-        R*) H=$((((${i:1}/90)+H)%4));;
-        L*) H=$((((-${i:1}/90)+H)%4));;
+        N*) ((Y+=n));;
+        S*) ((Y-=n));;
+        E*) ((X+=n));;
+        W*) ((X-=n));;
+        R*) ((H=((n/90)+H)%4));;
+        L*) ((H=((-n/90)+H)%4));;
         *) echo ERROR $i; break;;
     esac
 done
-echo "12A: $((X))+$((Y)) = $(((X<0?-X:X)+(Y<0?-Y:Y)))"
+echo "12A: $X+$Y = $((${X/-}+${Y/-}))"
 H=1; X=10; Y=1; x=0; y=0
 for i in "${A[@]}"; do
+    n=${i:1}
     case $i in
-        N*) Y+=+${i:1};;
-        S*) Y+=-${i:1};;
-        E*) X+=+${i:1};;
-        W*) X+=-${i:1};;
-        F*) x=$((x+${i:1}*(X))); y=$((y+${i:1}*(Y)));;
-        R90|L270)   TMP=$X; X=$((Y)); Y=$((-(TMP)));;
-        R270|L90)   TMP=$X; X=$((-(Y))); Y=$((TMP));;
-        R180|L180)  X=$((-(X)));Y=$((-(Y)));;
+        N*) ((Y+=n));;
+        S*) ((Y-=n));;
+        E*) ((X+=n));;
+        W*) ((X-=n));;
+        F*) ((x+=n*X,y+=n*Y));;
+        R90|L270)   TMP=$X; ((X=Y,Y=-TMP));;
+        R270|L90)   TMP=$X; ((X=-Y,Y=TMP));;
+        R180|L180)  ((X=-X,Y=-Y));;
         *) echo ERROR $i; break;;
     esac
 done
-echo "12B: $((x))+$((y)) = $(((x<0?-x:x)+(y<0?-y:y)))"
+echo "12B: $x+$y = $((${x/-}+${y/-}))"

13.sh

@@ -14,7 +14,7 @@ for i in ${!A[@]}; do [ ${A[i]} != x ] && B[$i]=${A[i]} ; done
 N=0; step=1
 #echo "${!B[@]} => "${B[@]}""
 for i in "${!B[@]}"; do
-    while [ $(( (N+i) % ${B[$i]})) != 0 ]; do N=$((N+step)); done
-    step=$((step*${B[$i]}))
+    while (((N+i)%${B[$i]})); do ((N+=step)); done
+    ((step*=${B[$i]}))
 done
 echo "13B: $N"

14.sh

@@ -13,14 +13,14 @@ echo "14A: $((sum))"
 r() {
     local x=${2/X/0}
     if [ "$x" = "$2" ]; then
-        mem2[$(($1|(2#$x)))]=$3
+        mem2[$1|(2#$x)]=$3
     else
         r $1 $x $3
         r $1 ${2/X/1} $3
     fi
 }
 
-IFS=$' []=\n\r'
+IFS=$' []=\n'
 while read i y _ v; do
    case "$i" in
        mask*) o=$((2#${y//X/0})); m=${y//1/0}; z=$((~2#${m//X/1}));;

15.sh

@@ -3,27 +3,27 @@ A=($(<${1:-15.txt}))
 GIVEUP=${2:-10}
 #A=(0 3 6)
 B=(); i=0; l=""
-for a in ${A[@]}; do B[$a]=$((++i)); done
+for a in ${A[@]}; do B[a]=$((++i)); done
 while [ $i -lt 2020 ]; do
-    n=$((i-${l:-$i})); l=${B[$n]}; B[$n]=$((++i))
+    n=$((i-${l:-$i})); l=${B[n]}; B[n]=$((++i))
 done
 echo "15A: $n"
 
 sharded_swap() { # syntax: l=B[$1]; B[$1]=$2
-#   local x="B$(($1>>9))[$(($1&511))]"
-    local x="B$(($1>>6))[$(($1&63))]"
+    local x="B$(($1>>9))[$1&511]"
+    #local x="B$(($1>>6))[$1&63]"
     eval "l=\${$x}; $x=$2"
 }
 SECONDS=0
+trap 'echo "$i: $SECONDS sec $((i/300000))%"' USR1 EXIT
 i=0; for a in ${A[@]}; do sharded_swap $a $((++i)); done; l="";
 while [[ $i -lt 30000000 && $SECONDS -le $GIVEUP ]]; do
     n=$((i-${l:-$i})); sharded_swap $n $((++i))
-    [ $((i%100000)) = 0 ] && echo "$i: $SECONDS sec"
 done
 if [ $i = 30000000 ]; then
     echo "15B: $n"
 else
-    # The code above would take days or weeks to run. Switch to awk
+    # The code above is painfully slow. Switch to awk
     echo "15B(round $i): $n (Gave up after $SECONDS seconds)"
     printf "%s\n" ${A[@]} | awk '{B[$0]=++i;}
 END {

16.sh

@@ -6,7 +6,7 @@ A=($(grep "," $input))
 sum=""
 for i in ${!A[@]}; do
   for j in ${A[i]//,/ }; do
-    [[ $j -lt $min || $j -gt $max ]] && sum+=+$j && A[i]=""
+    (( j < min || j > max )) && sum+=+$j && A[i]=""
   done
 done
 echo "16A: $((sum))"
@@ -27,8 +27,8 @@ for line in ${B[@]}; do
   T=(${line//,/ })
   for i in $idx; do
     for n in $idx; do
-      if [[ ${T[n]} -lt ${Cm1[i]} || ${T[n]} -gt ${CM1[i]} ]] && [[ ${T[n]} -lt ${Cm2[i]} || ${T[n]} -gt ${CM2[i]} ]]; then
-          Cf[$i]=${Cf[$i]//${f[n]}} # remove out of range char
+      if (( (T[n] < Cm1[i] || T[n] > CM1[i]) && (T[n] < Cm2[i] || T[n] > CM2[i]) )); then
+        Cf[i]=${Cf[i]//${f[n]}} # remove out of range char
       fi
     done
   done
@@ -39,8 +39,8 @@ while [[ "$oldC" != "${Cf[*]}" ]]; do
   oldC="${Cf[*]}"
   for i in $idx; do
     if [ ${#Cf[i]} = 1 ] ; then
-      x=${Cf[i]}; n=$((36#$i))
-      [ ${C[i]:0:3} = dep ] && total+=*${my_ticket[$n]}
+      x=${Cf[i]}
+      [ ${C[i]:0:3} = dep ] && total+=*${my_ticket[36#$i]}
       Cf=("${Cf[@]//$x}")
     fi
   done

18.sh

@@ -8,23 +8,22 @@ c() {
         if [[ $i = '+' || $i = '*' ]]; then
             op=$i
         else
-            sum=$((sum$op$i))
+            ((sum$op=$i))
         fi
     done
     #echo "c: ${*//[()]} = $sum " >&2
     echo ${sum}
 }
 
 IFS=$' \t\n'
-regex="\([^()]*\)"
+regex="\(([^()]*)\)"
 sum=""
 for line in "${A[@]}"; do
     while [[ "$line" =~ $regex ]]; do
-        k=${BASH_REMATCH[0]}
-        n=$(c "$k")
-        line="${line/${k//\*/\\*}/$n}" # stupid globbing
+        n=$(c ${BASH_REMATCH[1]})
+        line="${line/${BASH_REMATCH[0]//\*/\\*}/$n}" # stupid globbing
     done
-    sum+=+$(c "$line")
+    sum+=+$(c $line)
 done
 echo "18A: $((sum))"
 echo "18B: $(($(printf "+(%s)" "${A[@]//\*/)*(}")))"