ZOJ-3785

短命女 2022-05-26 03:45 149阅读 0赞

What day is that day?

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Time Limit: 2 Seconds       Memory Limit: 65536 KB

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It's Saturday today, what day is it after 11 + 22 + 33 + ... + NN days?

#### Input ####

There are multiple test cases. The first line of input contains an integer T indicating the number of test cases. For each test case:

There is only one line containing one integer N (1 <= N <= 1000000000).

#### Output ####

For each test case, output one string indicating the day of week.

#### Sample Input ####

2
    1
    2

#### Sample Output ####

Sunday
    Thursday

#### Hint ####

A week consists of Sunday, Monday, Tuesday, Wednesday, Thursday, Friday and Saturday.

题意：今天是周六，求1+2^2+3^3+…………n^n天后是周几；

思路：题目其实不难，一眼就可以看出来是找规律的题，也可以打表，但是如果打表的数据太小是找不到规律的，当我们把打表的值打到294时可以看到在后面就是对前面的循环，所以就可以得到规律；

代码：

#include<queue>
    #include<cmath>
    #include<cstdio>
    #include<cstring>
    #include<cstdlib>
    #include<iostream>
    #include<algorithm>
    using namespace std;
    #define ll long long
    int b[1000];
    char a[10][10]={"Saturday","Sunday","Monday","Tuesday","Wednesday","Thursday","Friday"};
    int main()
    {
        memset(b,0,sizeof(b));
        ll i,j,sum=0,ans=0;
        for(i=1;i<295;i++)
        {
            ans=1;
            for(j=1;j<=i;j++)
            {
                ans*=i;
                ans%=7;
            }
            b[i]=ans+b[i-1];
        }
    //    for(i=1;i<295;i++)
    //        printf("%d ",b[i]%7);
    //    printf("\n");
        int test;
        scanf("%d",&test);
        while(test--)
        {
            long long n,ans1=0;
            scanf("%lld",&n);
            ans1=b[n%294]%7;
            printf("%s\n",a[ans1]);
        }
        return 0;
    }