diff --git a/.gitignore b/.gitignore
index ba5a0fa..dec6035 100644
--- a/.gitignore
+++ b/.gitignore
@@ -25,5 +25,5 @@ _deps
 !*-sample.txt
 
 .vscode
-build
+build*
 release.*
diff --git a/src/MultField/mult-choose.cpp b/src/MultField/mult-choose.cpp
index faf2522..0a86824 100644
--- a/src/MultField/mult-choose.cpp
+++ b/src/MultField/mult-choose.cpp
@@ -186,7 +186,8 @@ int main() {
         }
     }
     sort(q.begin(), q.end());
-    maxLayer = 0;
+    maxLayer = 1;
+    for (int i = 0; i < C_num; i++) layer[i] = 0;
     for (int i = 0; i < (int)q.size(); i++) {
         layer[q[i].second] = 1;
         for (int j = 0; j < i; j++) if (layer[q[i].second] < layer[q[j].second] + 1) {
@@ -221,7 +222,8 @@ int main() {
         }
     }
     sort(q.begin(), q.end());
-    maxLayer = 0;
+    maxLayer = 1;
+    for (int i = 0; i < C_num; i++) layer[i] = 0;
     for (int i = 0; i < (int)q.size(); i++) {
         layer[q[i].second] = 1;
         for (int j = 0; j < i; j++) if (layer[q[i].second] < layer[q[j].second] + 1) {