diff --git a/src/nonlocal.jl b/src/nonlocal.jl
index eddcace..ae6fc89 100644
--- a/src/nonlocal.jl
+++ b/src/nonlocal.jl
@@ -45,13 +45,11 @@ function _local_bound_single(chunk, outs::NTuple{2, Int}, ins::NTuple{2, Int}, s
     ind = digits(chunk[1] - 1; base = ob, pad = ib)
     offset = Vector(1 .+ ob * (0:(ib - 1)))
     offset_ind = zeros(Int, ib)
-    Galice = zeros(T, oa * ia, 1)
-    maxvec = zeros(T, 1, ia)
+    Galice = zeros(T, oa * ia)
     @inbounds for _ in chunk[1]:chunk[2]
         offset_ind .= ind .+ offset
         @views sum!(Galice, squareG[:, offset_ind])
-        squareGalice = reshape(Galice, oa, ia)
-        temp_score = sum(maximum!(maxvec, squareGalice))
+        temp_score = _maxcols!(Galice, oa, ia)
         score = max(score, temp_score)
         _update_odometer!(ind, ob)
     end
@@ -63,8 +61,7 @@ function _local_bound_single(chunk, outs::NTuple{N, Int}, ins::NTuple{N, Int}, s
     score = typemin(T)
     bases = reduce(vcat, [outs[i] * ones(Int, ins[i]) for i in 2:length(ins)])
     ind = _digits_mixed_basis(chunk[1] - 1, bases)
-    Galice = zeros(T, outs[1] * ins[1], 1)
-    maxvec = zeros(T, 1, ins[1])
+    Galice = zeros(T, outs[1] * ins[1])
     b = zeros(Int, N - 1)
     sizes = (outs[2:N]..., ins[2:N]...)
     prodsizes = ones(Int, 2 * (N - 1))
@@ -83,12 +80,11 @@ function _local_bound_single(chunk, outs::NTuple{N, Int}, ins::NTuple{N, Int}, s
             for i in 1:(N - 1)
                 by[i + N - 1] = y[i] - 1
             end
-            for x in 1:ins[1], a in 1:outs[1]
-                Galice[a + (x - 1) * outs[1]] += squareG[a + (x - 1) * outs[1], linearindex(by)]
+            for i in 1:outs[1]*ins[1]
+                Galice[i] += squareG[i, linearindex(by)]
             end
         end
-        squareGalice = reshape(Galice, outs[1], ins[1])
-        temp_score = sum(maximum!(maxvec, squareGalice))
+        temp_score = _maxcols!(Galice, outs[1], ins[1])
         score = max(score, temp_score)
         _update_odometer!(ind, bases)
     end
@@ -96,6 +92,22 @@ function _local_bound_single(chunk, outs::NTuple{N, Int}, ins::NTuple{N, Int}, s
     return score
 end
 
+#sum(maximum(v, dims = 1)), with v interpreted as a oa x ia matrix
+function _maxcols!(v, oa, ia)
+    for x = 1:ia
+        for a = 2:oa
+            if v[a + (x-1)*oa] > v[1 + (x-1)*oa]
+                v[1 + (x-1)*oa] = v[a + (x-1)*oa]
+            end
+        end
+    end
+    temp_score = v[1]
+    for x = 2:ia
+        temp_score += v[1 + (x-1)*oa]
+    end
+    return temp_score
+end
+
 """
     partition(n::Integer, k::Integer)