1 files changed, 49 insertions, 0 deletions
diff --git a/shunting.py b/shunting.py
new file mode 100644
index 00000000..22d79f11
--- /dev/null
+++ b/shunting.py
@@ -0,0 +1,49 @@
+precedence = {
+    '-': 0,
+    '+': 0,
+    '*': 1,
+    '/': 1,
+}
+
+
+def shunting(inss: [str]):
+    op = []
+    out = []
+    for ins in inss:
+        if str.isnumeric(ins):
+            list.append(out, ins)
+        elif len(ins) == 1 and ins in "+-*/":
+            p = precedence[ins]
+            while op:
+                l = op[len(op) - 1]
+                if l == "(":
+                    break
+                pl = precedence[l]
+                if pl > p:
+                    out.append(op.pop())
+                else:
+                    break
+            op.append(ins)
+        elif len(ins) == 1 and ins in "mkbt":
+            out.append(ins)
+        elif ins == "(":
+            op.append(ins)
+        elif ins == ")":
+            while True:
+                if not op:
+                    raise "ILLEGAL PARENTHESIS"
+                l = op.pop()
+                if l == "(":
+                    break
+                out.append(l)
+        else:
+            raise f"UNKNOWN OP {ins}"
+    while op:
+        l = op.pop()
+        if l == "(":
+            raise "ILLEGAL PARENTHESIS"
+        out.append(l)
+    return out
+
+
+print(shunting("1 + 22 k * ( 3 + 4 ) k".split()))