Vigenère 密码

  这个名字实在打不来...

  题解:模拟

 1 #include <cstdio>
 2 #include <cstring>
 3 
 4 const int MAXL = 1000+10;
 5 
 6 bool cj;
 7 int cl, kl;
 8 char c[MAXL], k[MAXL], an;
 9 
10 int main(){
11     gets(k), gets(c);
12     kl = strlen(k), cl = strlen(c);
13     for (int i=0; i<kl; i++) 
14         if (k[i]<97) k[i] += 32;
15 
16     for (int i=0; i<cl; i++){
17         if (c[i]<97) c[i] += 32, cj = true; 
18         else cj = false;
19         an = (c[i]-'a'-(k[i%kl]-'a')+26)%26+'a';
20         if (cj) an -= 32;
21         printf("%c", an);
22     }
23 }
vigenere.cpp

 

国王游戏:

  题解:贪心+高精度,好吧,我看了wikioi的c++最快,这个方法简直....

 

 1 #include <cmath>
 2 #include <cstdio>
 3 #include <cstring>
 4 #include <algorithm>
 5 using std::sort;
 6 
 7 const int MAXN = 1000+10;
 8 const int MAXL = 100000+10;
 9 const int MOD = 10000;
10 
11 int n;
12 double sum[MAXN];
13 
14 struct bigInteger{
15     int len, a[MAXL];
16 
17     bigInteger(){
18         memset(a, 0, sizeof(a));
19         len = 0;
20     }
21 
22     inline void print(){
23         printf("%d", a[len]);
24         for (int i=len-1; i>=1; i--)
25             printf("%04d", a[i]);
26         printf("\n");
27     }
28 }Pri;
29 
30 struct Minister{
31     int l, r;
32     double sm;
33 
34     friend bool operator < (const Minister& a, const Minister& b){
35         return a.sm<b.sm;    
36     }
37 }mt[MAXN];
38 
39 void operator *= (bigInteger& a, int b){
40     for (int i=1, c=0, t; i<=a.len+2; i++)
41         t = a.a[i]*b+c,
42         a.a[i] = t%MOD,
43         c = t/MOD;
44     
45     while (a.a[a.len+1]) a.len ++;
46 }
47 
48 void operator /= (bigInteger& a, int b){
49     for (int i=a.len, c=0; i>=1; i--)
50         c = c*MOD+a.a[i],
51         a.a[i] = c/b,
52         c %= b;
53     while (!a.a[a.len] && a.len>1) -- a.len;
54 }
55 
56 int main(){
57     scanf("%d", &n);
58     for (int i=0; i<=n; i++)
59         scanf("%d %d", &mt[i].l, &mt[i].r),
60         mt[i].sm = log(mt[i].l)+log(mt[i].r);
61      
62     sort(mt+1, mt+n+1);
63 
64     double t;
65     sum[0] = log(mt[0].l);
66     for (int i=1; i<=n; i++)
67         t = log(mt[i].l),
68         sum[i] = sum[i-1]+t;
69 
70     int k = 0;
71     t = -1;
72     for (int i=1; i<=n; i++)
73         if (sum[i-1]-log(mt[i].r)>t)
74             k = i, t = sum[i-1]-log(mt[i].r);
75 
76     Pri.len = 1, Pri.a[1] = 1;
77     for (int i=0; i<k; i++)
78         Pri *= mt[i].l;
79     Pri /= mt[k].r;
80     Pri.print();
81 }
game.cpp

 

同余方程

  题解:我只会用扩展欧几里得解...

 1 #include <cstdio>
 2 
 3 int a, b, x, y, t;
 4 
 5 inline void ExGcd(int a, int b){
 6     if (b==0) return;
 7     ExGcd(b, a%b);
 8     t = x, x = y, y = t-(a/b)*x;
 9 }
10 
11 int main(){
12     scanf("%d %d", &a, &b), x = 1, y = 0;
13     ExGcd(a, b);
14     while (x<=0) x += b;
15     printf("%d", x);
16 }
mod.cpp

 

借教室

  题解:二分。开始没加读入优化,在vijos上TLE了...

 1 #include <cstdio>
 2 #include <cstring>
 3 
 4 const int MAXN = 1e6+10;
 5 
 6 struct Indent{
 7     int l, r, n;    
 8 }d[MAXN];
 9 
10 int n, m, mid, temp[MAXN], lim[MAXN];
11 char c;
12 
13 inline int NextInt(){
14     int ret = 0;
15     do
16         c = getchar();
17     while (!(48<=c && c<=57));
18     
19     do
20         ret *= 10, ret += c-48, c = getchar();
21     while (48<=c && c<=57);
22 
23     return ret;
24 }
25 
26 inline bool Check(int x){
27     memset(temp, 0, sizeof(temp));
28 
29     int sum = 0;
30     for (register int i=1; i<=x; i++)
31         temp[d[i].l] += d[i].n, temp[d[i].r+1] -= d[i].n;
32     for (register int i=1; i<=n; i++){
33         sum += temp[i];
34         if (sum>lim[i]) return false;
35     }
36     return true;
37 }
38 
39 int main(){
40     n = NextInt(), m = NextInt();
41     for (register int i=1; i<=n; i++)
42         lim[i] = NextInt();
43     for (register int i=1; i<=m; i++)
44         d[i].n = NextInt(), d[i].l = NextInt(), d[i].r = NextInt();
45             
46     int l = 1, r = m+1, mid;
47     while (l<r){
48         mid = (l+r)>>1;
49         if (Check(mid)) l = mid+1;
50         else r = mid;
51     }
52     if (l<m) printf("-1\n%d", l);
53     else printf("0");
54 }
classroom.cpp
Posted on 2014-07-22 10:46  cjhahaha  阅读(106)  评论(0编辑  收藏