CSP_J_2021 第一轮认证题

solve(n)
if n<=1 return 1
else if n>=5 return n*solve(n-2)
else return n*solve(n-1)

01 #include <iostream>
02 using namespace std;
03
04 int n;
65 int a[1088];
06
07 int f(int x)
08 {
09  int ret=0; 
10  for (;x; x &= x - 1) ret++;
11   return ret;
12 }
13
14  int g(int x)
15 {
16   return x & -x;
17 }
18
19 int main()
20 { cin >> n;
22   for (int i =0;i < n; i++) cin >> a[i];
23   for (inti=0;i< n; i++)
24  cout << f(a[i]) + g(a[i]) <<'';
25    cout << endl;
26    return 0;

01 #include <iostream>
02 #include <string>
03 using namespace std;
04
05 char base[64];
06 char table[256];
07
08 void init()
09 {
10     for (int i = 0;i< 26;i++) base[i] ='A'+ i;
11     for (int i= 0; i<26;i++) base[26 + i]='a'+ i;
12     for (int i =0;i< 10; i++) base[52 + i] ='0'+ i;
13     base[62]='+'，base[63] ='/;
14
15     for (int i=0;i< 256; i++) table[i] = 0xff;
16     for (int i=0;i< 64; i++) table[base[i]] = i;
17     table['=']= 0;
18 }
19
20 string decode(string str)
21 {
22 string ret;
23  int i;
24  for (i=0;i < str.size(); i += 4){
25    ret += table[str[i]] << 2 | table[str[i + 1]] >> 4;
26    if (str[i + 2] !='=')
27         ret += (table[str[i + 1]] & 0x0f) << 4 | table[str[i +2]] >> 2;
28    if (str[ + 3] !='=')
29         ret += table[str[i + 2]] << 6 | table[str[i + 3]];
30 }
31 return ret;
32 }
33
34 int main()
35 (
36  init();
37  cout << int(table[e]) << endl;
38
39  string str;
40  cin >> str;
41  cout << decode(str) << endl;
42  return 0;
43 }

01 #include <iostream>
02 using namespace std;
03
04 const int n = 100000;
05 const int N = n + 1;
06
07 int m;
08 int a[N],b[N],c[N],d[N];
09 int f[N],g[N];
10
11 void init()
12 {
13   f[1]= g[1]=1;
14   for (int i= 2;i <=n;i++){
15        if (!a[i]){
16            b[m++] =i;
17              c[i]= 1,f[i]=2;
18              d[i]= 1,g[i]=i+1; 
19  }
20    for (int j= 0;j< m && b[j]*i<= n; j++){
21      int k m b[j]; 
22          a[i*k]=1;
23         if (i% k == 0) {
24             c[i* k]= c[i]+ 1;
25             f[i*k]=f[i] / c[i*k] * (c[i*k]+1);
26        d[i*k]= d[i];
27              g[i*k]=g[i]*k+d[i];
28              break;
29          }
30         else {
31   c[i*k]=1;
32   f[i*k]=2*f[i];
33   d[i*k]= g[i];
34   g[i*k]=g[i]*(k+1);
35       }
36     }
37   }
38 }
39
40  int main()
41 {
42   init();
43
44   int x;
45   cin >> x;
46   cout << f[x] <<'  '<< g[x] << endl;
47 return 0;
48 }

01 #include <iostream>
02
03 using namespace std;
04
05 const int MAXN = 1000000;
06 int F[MAXN];
07
08 int main() (
09 int n;
10 cin >> n;
11 int i=0,p=0,c=0;
12 while (  1  ){
13   if ( F[i] == 0){
14     if( 2 ){
15         F[i] = 1;
16         3
17       }
18         4
19      }
20      5
21 }
22  int ans = -1;
23  for (i=0;1<n;i++)
24     if (F[i]==0)
25         ans = i;
26    cout << ans << endl;
27     return 0; 
28 }

01 #include <iostream>
02
03 using namespace std;
04
05 struct point {
06  int x,y, id;
07 };
08
09 bool equals(point a, point b) {
10  return a.x == b.x && a.y == b.y;
11 }
12
13 bool cmp(point a,point b) {
14 return 1;
15 }
16
17 void sort(point A[],int n) {
18  for (int i=;i<n; i++)
19   for (int j= 1;j< n;j++)
20    if (cmp(A[j],A[j - 1])){
21     point t = A[j];
22     A[j] = A[j- 1]
23     A[j-1] =t;
24  }
25 }
26
27 int unique(point A[],int n) {
28  int t =0;
29  for (int i =0;i < n; i++)
30           if(2)
31    A[t++]A[i];
32  return t;
33 }
34
35 bool binary_search(point A[],int n,int xint y) {
36  point p; 
37  p.X = X;
38  p.y = y;
39  p.id =n;
40  int a=0,b=n- 1;
41  while (a < b) {
42      int mid = 3;
43   if( 4 )
44    a = mid + 1;
45   else
46    b = mid;
46
47       }
48 return equals(A[a],p);
49 }
50
51 const int MAXN = 100;
52 point A[MAXN];
53
54 int main() {
55  int n;
56  cin >> n;
57  for (int i=0;i < n; i++) {
58   cin >> A[1].x >> A[i].y;
59           A[i].id = i;
60  }
61 sort(A，n);
62 n = unique(A,n);
63 int ans = 0;
64 for (int i=0 ;i< n;i++)
65  for (int j= 0;j< n; j++)
66   if (5  && binary_search(A,n,A[i].x,A[j].y) && binary_search(A,n,A[j].x,A[i].y)){
67    ans++;
68   }
69 cout << ans << endl;
70 return 0;
71  }