JakeLin- [ACM training] interesting game-problem / easy to understand

Title Description
In order to enrich the extracurricular life of party members, the Academy organized a contest to learn the knowledge of a strong country. The scoring rules of the contest are: each player has a starting score of 10 points, and the contestants need to answer 10 questions (numbered 1 to 10) , The answer is correct, the current score is doubled, if the answer is wrong, the score with the same question number will be deducted.

Input

The first line has an integer M (1 <= M <100) means there are M sets of test data; then each line enters a score score (0≤score≤100)

Output

Assuming that you have not watched the game, please output the number of possible situations for each score, and output -1 if there are no possible situations. (Hint: If 0 represents the player ’s wrong question, 1 represents the player ’s correct question, and the player ’s final score is 90, there may be the following two situations
1110000010
0001110110)

Sample input

3
68
63
100

Sample output

7
-1
3

Original title link: Interesting game

 

Observed:

0000000000 -> 0
0000000001 -> 1
0000000010 -> 2
…
1111111111 -> 1023

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Find:

You only need to traverse 0 ~ 1023 to get all the cases, and judge whether each case meets the entered score.

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need you:

• 1. Grasp the decimal number to binary number (% 2 each time)
• 2. The front vacancy needs to be filled with 0 (the whole is set to 0, and the result of inserting% 2 from the back)

#include<cstdio>
#include<cstring>
#include<iostream>
using namespace std;
int main() {
    int m;
    cin>>m;
    int a[10];
    while(m--) {
        int score;
        cin>>score;
        int cnt=0;
        for(int i=0; i<=1023; i++) {
            memset(a,0,sizeof(a));
            int p=9;
            int t=i;
            while(t) {
                a[p--]=t%2;
                t/=2;
            }
            int s = 10;
            for(int j=0; j<10; j++) {
                if(a[j]==0) s-=(j+1);
                else s*=2;
            }
            if(score==s) cnt++;
        }
        if(cnt==0) cout<<-1<<endl;
        else cout<<cnt<<endl;
    }
    return 0;
}