LightOJ 1078 - Integer Divisibility【同余】

╰+攻爆jí腚メ 2022-08-18 02:07 16阅读 0赞

1078 - Integer Divisibility

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   <td style="background:rgb(245,250,250); font:bold 11px/normal 'Trebuchet MS',Verdana,Arial,Helvetica,sans-serif; padding:6px 6px 6px 12px; text-align:center; color:rgb(121,114,104); border-right-color:rgb(193,218,215); border-bottom-color:rgb(193,218,215); border-right-width:1px; border-bottom-width:1px; border-right-style:solid; border-bottom-style:solid"> Memory Limit:&nbsp;<span style="color:rgb(180,95,4)">32 MB</span></td> 
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If an integer is not divisible by 2 or 5, some multiple of that number in decimal notation is a sequence of only a digit. Now you are given the number and the only allowable digit, you should report the number of digits of such multiple.

For example you have to find a multiple of 3 which contains only 1's. Then the result is 3 because is 111 (3-digit) divisible by 3. Similarly if you are finding some multiple of 7 which contains only 3's then, the result is 6, because 333333 is divisible by 7.

# Input #

Input starts with an integer **T (≤ 300)**, denoting the number of test cases.

Each case will contain two integers **n (0 < n ≤ 106** and **n** will not be divisible by **2** or **5**) and the allowable digit **(1 ≤ digit ≤ 9)**.

# Output #

For each case, print the case number and the number of digits of such multiple. If several solutions are there; report the minimum one.

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   <td style="padding:0in 5.4pt; border:1pt solid black; width:239.4pt"> <h1 style="font:bold 14pt/21.46px Cambria,serif; margin:0in 0in 0pt; text-align:justify; color:green; page-break-after:avoid"> Sample Input</h1> </td> 
   <td style="border-style:solid solid solid none; padding:0in 5.4pt; width:239.4pt; border-top-color:black; border-right-color:black; border-bottom-color:black; border-top-width:1pt; border-right-width:1pt; border-bottom-width:1pt"> <h1 style="font:bold 14pt/21.46px Cambria,serif; margin:0in 0in 0pt; text-align:justify; color:green; page-break-after:avoid"> Output for Sample Input</h1> </td> 
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   <td style="border-style:none solid solid; padding:0in 5.4pt; width:239.4pt; height:36.85pt; border-right-color:black; border-bottom-color:black; border-left-color:black; border-right-width:1pt; border-bottom-width:1pt; border-left-width:1pt"> <p style="margin:0in 0in 0pt; font-family:Garamond,serif; font-size:12pt"> <span style="font-family:'Courier New'">3</span></p> <p style="margin:0in 0in 0pt; font-family:Garamond,serif; font-size:12pt"> <span style="font-family:'Courier New'">3 1</span></p> <p style="margin:0in 0in 0pt; font-family:Garamond,serif; font-size:12pt"> <span style="font-family:'Courier New'">7 3</span></p> <p style="margin:0in 0in 0pt; font-family:Garamond,serif; font-size:12pt"> <span style="font-family:'Courier New'">9901 1</span></p> </td> 
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解题思路

题目的大意就是看看有多少个M可以让N整除。

#include<stdio.h>
    #include<string.h>
    #include<algorithm>
    using namespace std;
    int main()
    {
    	int t;
    	scanf("%d",&t);
    	int yy=0;
    	while(t--)
    	{
    		yy++;
    		long long a,b;
    		scanf("%lld%lld",&a,&b);
    		long long map=b%a;
    		long long ans=1;
    		while(map)
    		{
    			map=(map*10+b)%a;
    			ans++;
    		}
    		printf("Case %d: %lld\n",yy,ans);
    	}
    	return 0;
    }