Update 素数.cpp

素数.cpp

@@ -1,18 +1,18 @@
 
 #include <stdio.h>
-#include <math.h>//ʹsqrt<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 
+#include <math.h>//使sqrt可以正常运行 
 int prime(int n)
 {
 int i ,m = 0;
-if(n==0||n==1)//<EFBFBD>ж<EFBFBD>0<EFBFBD><EFBFBD>1<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 
+if(n==0||n==1)//判断0和1的情况 
 return 0;
 else
 {
-for (i = 2; i <= sqrt(n); i++)//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>ѭ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ԭ<EFBFBD><EFBFBD>Ϊһ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>б<EFBFBD>ƽ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 
+for (i = 2; i <= sqrt(n); i++)//减少循环次数，原理为一个数不可能有比平方根大的因子 
 {
 if (n%i == 0)
 {
-    m++;//m<EFBFBD><EFBFBD>Ϊ0ʱ˵<EFBFBD><EFBFBD>n<EFBFBD><EFBFBD><EFBFBD><EFBFBD>1<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>֮<EFBFBD>⻹<EFBFBD>б<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>ӣ<EFBFBD><EFBFBD><EFBFBD><EFBFBD>Բ<EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD> 
+    m++;//m不为0时说明n除了1和它本身之外还有别的因子，所以不是素数 
 }
 }
 if(m==0)
@@ -30,7 +30,7 @@ int main()
 {
 int num = 0;
 scanf("%d", &num);
-if (prime(num))//<EFBFBD><EFBFBD><EFBFBD><EFBFBD>prime<EFBFBD><EFBFBD><EFBFBD><EFBFBD> 
+if (prime(num))//调用prime函数 
 {
 printf("Yes");
 }
@@ -39,3 +39,5 @@ printf("No");
 return 0;
 }
 
+
+