usaco-crypt1-pass

这个想了半天，终于过了：

/*
ID: qq104801
LANG: C++
TASK: crypt1
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

void debug_dummy()
{
    return;
}

int n;
int d[10];

int numlen(int x)
{    
    int l=1;
    while(x/10)
    {
        l++;
        x/=10;
    }
    //printf("%d %d
",x,l);
    return l;
}

bool iscrypt(int x,int m)
{   
    while(m--)
    {
        if(!d[x%10] || x==0)
            return false;
        x/=10;        
    } 
    if (x!=0)return false;   
    return true;
}

bool check(int a,int b)
{
    int p,q;
    p=a*(b/10);
    q=a*(b%10);
    if (!iscrypt(a,3) || !iscrypt(b,2) || !iscrypt(a*b,4))
        return false;
    if (!iscrypt(p,3) || !iscrypt(q,3) )
        return false;
    return true;
}

void test()
{
    int sum=0;
    FILE *fin = fopen ("crypt1.in", "r");
    FILE *fout = fopen ("crypt1.out", "w"); 
    fscanf(fin,"%d",&n);
    for(int i=0;i<10;i++)
        d[i]=0;
    for(int i=0;i<n;i++)
    {
        int t;
        fscanf(fin,"%d",&t);
        d[t]=1;
        //printf("%d %d
",t,d[t]);        
    }
    for(int i=100;i<1000;i++)
        for(int j=10;j<100;j++)
        {
            if ((i==222) && (j==22))
                debug_dummy();
            if (check(i,j))
            {
                sum++;
                //printf("%d*%d=%d ==>%d   p1:%d p2:%d
",i,j,i*j,i*(j%10)+i*(j/10)*10,i*(j%10),i*(j/10));
            }
        }
    //printf("sum:%d
",sum);
    fprintf(fout,"%d
",sum);
    fclose(fin);
    fclose(fout);
}

main () {    
    test();    
    exit (0);
}

测试用例：

USER: ll tom [qq104801]
TASK: crypt1
LANG: C++

Compiling...
Compile: OK

Executing...
   Test 1: TEST OK [0.011 secs, 3500 KB]
   Test 2: TEST OK [0.008 secs, 3500 KB]
   Test 3: TEST OK [0.008 secs, 3500 KB]
   Test 4: TEST OK [0.011 secs, 3500 KB]
   Test 5: TEST OK [0.005 secs, 3500 KB]
   Test 6: TEST OK [0.003 secs, 3500 KB]
   Test 7: TEST OK [0.014 secs, 3500 KB]

All tests OK.

Your program ('crypt1') produced all correct answers! This is your submission #4 for this problem. Congratulations!

Here are the test data inputs:

------- test 1 ----
5
2 3 4 6 8
------- test 2 ----
4
2 3 5 7
------- test 3 ----
1
1
------- test 4 ----
7
4 1 2 5 6 7 3
------- test 5 ----
8
9 1 7 3 5 4 6 8
------- test 6 ----
6
1 2 3 5 7 9
------- test 7 ----
9
1 2 3 4 5 6 7 8 9

Keep up the good work!
Thanks for your submission!