二、阅读题

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13

#include <stdio.h>
int main() {
    int x;
    scanf("%d", &x);
    int res = 0;
    for (int i = 0; i < x; ++i) {
        if (i * i % x == 1) {
        	++res;
        }
    }
    printf("%d", res);
    return 0;
}

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

#include <stdio.h>

int n, d[100];
bool v[100];

int main() {
    scanf("%d", &n);
    for (int i = 0; i < n; ++i) {
        scanf("%d", d + i);
        v[i] = false;
    }
    int cnt = 0;
    for (int i = 0; i < n; ++i) {
        if (!v[i]) {
            for (int j = i; !v[j]; j = d[j]) {
            	v[j] = true;
            }
            ++cnt;
        }
    }
    printf("%d\n", cnt);
    return 0;
}

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35

#include <iostream>
using namespace std;
string s;

long long magic(int l, int r) {
    long long ans = 0;
        for (int i = l; i <= r; ++i) {
        ans = ans * 4 + s[i] - ‘a’ + 1;
    }
return ans;
}

int main() {
    cin >> s;
    int len = s.length();
    int ans = 0;
    for (int l1 = 0; l1 < len; ++l1) {
        for (int r1 = l1; r1 < len; ++r1) {
            bool bo = true;
            for (int l2 = 0; l2 < len; ++l2) {
                for (int r2 = l2; r2 < len; ++r2) {
                    if (magic(l1, r1) == magic(l2, r2) 
                    	&& (l1 != l2 || r1 != r2)) 
                    	bo = false;
                }
            }
            
            if (bo) {
                ans += 1;
            }
        }
    }
    cout << ans << endl;
    return 0;
}

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50

#include <iostream>
using namespace std;
const int N = 110;
bool isUse[N];
int n, t;
int a[N], b[N];
bool isSmall() {
    for (int i = 1; i <= n; ++i)
        if (a[i] != b[i]) return a[i] < b[i];
    return false;
}
bool getPermutation(int pos) {
    if (pos > n) {
        return isSmall();
    }
    for (int i = 1; i <= n; ++i) {
        if (!isUse[i]) {
            b[pos] = i; isUse[i] = true;
            if (getPermutation(pos + 1)) {
                return true;
            }
            isUse[i] = false;
        }
    }
    return false;
}
void getNext() {
    for (int i = 1; i <= n; ++i) {
        isUse[i] = false;
    }
    getPermutation(1);
    for (int i = 1; i <= n; ++i) {
        a[i] = b[i];
    }

}
int main() {
    scanf("%d%d", &n, &t);
    for (int i = 1; i <= n; ++i) {
        scanf("%d", &a[i]);
    }
    for (int i = 1; i <= t; ++i) {
        getNext();
    }
    for (int i = 1; i <= n; ++i) {
        printf("%d", a[i]);
        if (i == n) putchar(’\n’); else putchar(’ ');
    }
    return 0;
}