fix(tool/judgers.md): wrong usage in building lemon

1.  we can pass parameter into `./make` instead of using `sed` to modify the file,
    `-jn` can be passed although `-j n` can't.
2.  we can install the executable file into PATH instead of throwing it into home dir.

the result of git blame: https://github.com/OI-wiki/OI-wiki/commit/47acc594f2d94423d319a7b1ee83546ad29552a6

diff --git a/docs/tools/judgers.md b/docs/tools/judgers.md
index 3ff5b23..9cc2bbc 100644 (file)
--- a/docs/tools/judgers.md
+++ b/docs/tools/judgers.md
@@ -174,13 +174,11 @@ Ubuntu：
 ```bash
 sudo apt update
 sudo apt install qt5-default build-essential git -y
-git clone --depth=1 http://github.com/menci/lemon.git
+git clone --depth=1 https://github.com/Menci/Lemon.git
 cd lemon
-# 可以修改 make 文件来调整 make job 的线程数
-sed -i 's/make $/make -j 1 $/g' make
-./make
-cp Lemon ~
-cd ..
+# 可以修改 -j 后面的数字来调整 make job 的线程数
+./make -j2
+sudo install -Dm755 -t /usr/bin/ Lemon
 ```
 
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