Compress code (2)

lua/src/lib/math.lua

@@ -1,8 +1,7 @@
 local function factorial(n)
     local answer = 1
 
-    for i = 2,n,1
-    do
+    for i = 2,n do
         answer = answer * i
     end
 
@@ -13,28 +12,22 @@ local function factor_gen(n, r)
     local factors = {}
 
     -- collect factors of final number
-    for i = 2,n,1
-    do
+    for i = 2,n do
         factors[i] = 1
     end
 
     -- negative factor values indicate need to divide
-    for i = 2,r,1
-    do
+    for i = 2,r do
         factors[i] = factors[i] - 1
     end
-    for i = 2,(n - r),1
-    do
+    for i = 2,(n - r) do
         factors[i] = factors[i] - 1
     end
 
     -- this loop reduces to prime factors only
-    for i = n,2,-1
-    do
-        for j = 2,(i - 1),1
-        do
-            if i % j == 0
-            then
+    for i = n,2,-1 do
+        for j = 2,(i - 1) do
+            if i % j == 0 then
                 factors[j] = factors[j] + factors[i]
                 factors[i / j] = factors[i / j] + factors[i]
                 factors[i] = 0
@@ -47,8 +40,7 @@ local function factor_gen(n, r)
 end
 
 local function n_choose_r(n, r)
-    if n < 20  -- fast path if number is small
-    then
+    if n < 20 then -- fast path if number is small
         return factorial(n) / factorial(r) / factorial(n - r)
     end
 
@@ -59,36 +51,29 @@ local function n_choose_r(n, r)
     local i = 2
     local j = 2
     answer = 1;
-    while i <= n
-    do
-        while factors[i] > 0
-        do
+    while i <= n do
+        while factors[i] > 0 do
             tmp = answer
             answer = answer * i
-            while answer < tmp and j <= n
-            do
-                while factors[j] < 0
-                do
+            while answer < tmp and j <= n do
+                while factors[j] < 0 do
                     tmp = math.floor(tmp / j)
                     factors[j] = factors[j] + 1
                 end
                 j = j + 1;
                 answer = tmp * i
             end
 
-            if answer < tmp
-            then
+            if answer < tmp then
                 return nil, "math error: overflow"
             end
             factors[i] = factors[i] - 1
         end
         i = i + 1
     end
 
-    while j <= n
-    do
-        while factors[j] < 0
-        do
+    while j <= n do
+        while factors[j] < 0 do
             answer = answer / j
             factors[j] = factors[j] + 1
         end

lua/src/lib/primes.lua

@@ -6,13 +6,10 @@ local function primes(stop)
     local function next_prime(cand)
         local steps = sieve[cand]
 
-        if steps
-        then
-            for _, step in ipairs(steps)
-            do
+        if steps then
+            for _, step in ipairs(steps) do
                 local value = cand + step
-                if sieve[value]
-                then
+                if sieve[value] then
                     table.insert(sieve[value], step)
                 else
                     sieve[value] = { step }
@@ -27,8 +24,7 @@ local function primes(stop)
     end
 
     local function next()
-        if stop and prime >= stop
-        then
+        if stop and prime >= stop then
             sieve = {}
             error("Tried to exceed given limit")
         end
@@ -48,23 +44,19 @@ local function prime_factors(n)
     local p = pgen.next()
 
     local function next()
-        if n == 1
-        then
+        if n == 1 then
             return nil
         end
 
-        while p and n % p
-        do
+        while p and n % p ~= 0 do
             p = pgen.next()
         end
 
-        if p == nil
-        then
+        if p == nil then
             return nil
         end
 
-        if n < 0
-        then
+        if n < 0 then
             n = -n
             return -1
         end

lua/src/lib/range.lua

@@ -6,19 +6,15 @@ end
 
 local function range_entry4(start, stop, step, idx)
     local length = 0
-    if step > 0 and start < stop
-    then
+    if step > 0 and start < stop then
         length = math.floor(1 + (stop - 1 - start) / step)
-    elseif step < 0 and start > stop
-    then
+    elseif step < 0 and start > stop then
         length = math.floor(1 + (start - 1 - stop) / (-step))
     end
-    if idx < 0
-    then
+    if idx < 0 then
         idx = length + idx
     end
-    if idx < 0 or idx >= length
-    then
+    if idx < 0 or idx >= length then
         return nil, "length is 0, cannot fetch"
     end
     return range_entry3(start, step, idx)

lua/src/p0017.lua

@@ -19,7 +19,7 @@ local function to_string_len(n)
     if n >= 1000 then
         local thousands = to_string_len(math.floor(n / 1000 % 100)) + 8
 
-        if n % 1000 then
+        if n % 1000 ~= 0 then
             thousands = thousands + to_string_len(n % 1000)
         end
 
@@ -29,7 +29,7 @@ local function to_string_len(n)
     if n >= 100 then
         local hundreds = to_string_len(math.floor(n / 100 % 10)) + 7
 
-        if n % 100 then
+        if n % 100 ~= 0 then
             hundreds = hundreds + 3 + to_string_len(n % 100)
         end
 
@@ -49,7 +49,7 @@ local function to_string_len(n)
         }
         local tens = tens_t[math.floor(n / 10)]
 
-        if n % 10 then
+        if n % 10 ~= 0 then
             tens = tens + to_string_len(n % 10)
         end