1 files changed, 75 insertions, 0 deletions
diff --git a/tests/performance/19_radix_sort.sy b/tests/performance/19_radix_sort.sy
new file mode 100644
index 0000000..d8e1cee
--- /dev/null
+++ b/tests/performance/19_radix_sort.sy
@@ -0,0 +1,75 @@
+// 你可以用这个生成数据
+// import numpy as np
+//
+// print(2000000)
+// for x in np.random.choice(2000000, 2000000):
+//     print(x, end=' ')
+
+int n;
+int aux[2000000];
+
+
+void radix_sort(int a[], int n) {
+  const int U = 65536;
+  int i;
+  // 不行, segment fault
+  // int cnt[65536] = {};
+  // 可以
+  int cnt[65536];
+
+  i = 0;
+  while (i < U) {
+    cnt[i] = 0;
+    i = i + 1;
+  }
+
+  i = 0;
+  while (i < n) {
+    cnt[a[i] % U] = cnt[a[i] % U] + 1;
+    i = i + 1;
+  }
+  i = 1;
+  while (i < U) {
+    cnt[i] = cnt[i] + cnt[i - 1];
+    i = i + 1;
+  }
+  i = n - 1;
+  while (i >= 0) {
+    cnt[a[i] % U] = cnt[a[i] % U] - 1;
+    aux[cnt[a[i] % U]] = a[i];
+    i = i - 1;
+  }
+
+  i = 0;
+  while (i < U) {
+    cnt[i] = 0;
+    i = i + 1;
+  }
+
+  i = 0;
+  while (i < n) {
+    cnt[aux[i] / U % U] = cnt[aux[i] / U % U] + 1;
+    i = i + 1;
+  }
+  i = 1;
+  while (i < U) {
+    cnt[i] = cnt[i] + cnt[i - 1];
+    i = i + 1;
+  }
+  i = n - 1;
+  while (i >= 0) {
+    cnt[aux[i] / U % U] = cnt[aux[i] / U % U] - 1;
+    a[cnt[aux[i] / U % U]] = aux[i];
+    i = i - 1;
+  }
+}
+
+int main(){
+  starttime();
+  int a[2000000];
+  n = getarray(a);
+  radix_sort(a, n);
+  putarray(n, a);
+  stoptime();
+  return 0;
+}
+\ No newline at end of file