Merge pull request #64 from yomaytk/add-examples

Add prime calculation example.

examples/benchmarks/eratosthenes_sieve/Makefile

@@ -0,0 +1,15 @@
+CC=clang-18
+GCC=gcc
+
+eratosthenes_sieve: main.c
+	@ARCH=$$(uname -m); \
+	if [ "$$ARCH" = "x86_64" ]; then \
+			$(CC) -static --target=aarch64-linux-gnu --gcc-toolchain=/usr --sysroot=/usr/aarch64-linux-gnu main.c -fuse-ld=lld -pthread; \
+	elif [ "$$ARCH" = "aarch64" ]; then \
+			$(GCC) -O3 -static main.c -o a_o3.aarch64; \
+	else \
+			echo "Unknown architecture"; exit 1; \
+	fi
+
+clean:
+	rm *.out

examples/benchmarks/eratosthenes_sieve/main.c

@@ -0,0 +1,88 @@
+#include <float.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+#define MAX_NUM 10000000
+
+int digit_num(int num) {
+  int res = 0;
+  for (;;) {
+    if (num > 0) {
+      num /= 10;
+      res++;
+    } else {
+      break;
+    }
+  }
+  return res;
+}
+
+int mhex(int num) {
+  int res = 1;
+  for (;;) {
+    if (num / res > 9) {
+      res *= 10;
+    } else {
+      break;
+    }
+  }
+  return res;
+}
+
+static double second(void)
+
+{
+  return ((double) ((double) clock() / (double) CLOCKS_PER_SEC));
+}
+
+int main() {
+
+  double t1 = second();
+
+  printf("t1: %f\n", t1);
+
+  double tt1 = second();
+
+  printf("tt1: %f\n", tt1);
+
+  int *nums = (int *) malloc(MAX_NUM * sizeof(int));
+  char s[100];
+
+  nums[0] = nums[1] = 0;
+  for (int i = 2; i < MAX_NUM; i++) {
+    nums[i] = 1;
+  }
+
+  // cal
+  for (int base = 2; base < 1000; base++) {
+    if (!nums[base]) {
+      continue;
+    }
+    for (int target = base * 2; target < MAX_NUM; target += base) {
+      nums[target] = 0;
+    }
+  }
+  int seek;
+  for (int i = 0; i < MAX_NUM; i++) {
+    if (!nums[i]) {
+      continue;
+    }
+    int mm = mhex(i);
+    seek = 0;
+    for (int j = i; j > 0;) {
+      s[seek++] = '0' + (j / mm);
+      j -= mm * (j / mm);
+      mm /= 10;
+    }
+  }
+  s[seek] = '\n';
+
+  double t2 = second();
+  printf("t2: %f\n", t2);
+
+  // // stdout
+  printf("max prime: %s", s);
+  printf("time: %f\n", t2 - tt1);
+}