'commit'

TangDou/AcWing/RongChi/HDU2204_2.cpp

@@ -2,27 +2,27 @@
 using namespace std;
 #define ll long long
 const int N = 100 + 100;
-ll mu[N * 100], prim[N * 100], check[N * 100];
-int tot;
+ll mu[N * 100], primes[N * 100], st[N * 100];
+int cnt;
 
 void get_mobius() {
     mu[1] = 1;
     for (int i = 2; i < N; i++) {
-        if (!check[i]) {
-            prim[tot++] = i;
+        if (!st[i]) {
+            primes[cnt++] = i;
             mu[i] = -1;
         }
-        for (int j = 0; j < tot; j++) {
-            if (prim[j] > N / i) {
+        for (int j = 0; j < cnt; j++) {
+            ll t = primes[j] * i;
+            if (primes[j] > N / i) {
                 break;
             }
-            check[i * prim[j]] = 1;
-            if (i % prim[j] == 0) {
-                mu[i * prim[j]] = 0;
+            st[t] = 1;
+            if (i % primes[j] == 0) {
+                mu[t] = 0;
                 break;
-            } else {
-                mu[i * prim[j]] = -mu[i];
             }
+            mu[t] = -mu[i];
         }
     }
 }