Codeforces 371C - Sonya and Queries(思維)__CodeForces

C. Sonya and Queries
time limit per test1 second
memory limit per test256 megabytes
inputstandard input
outputstandard output
Today Sonya learned about long integers and invited all her friends to share the fun. Sonya has an initially empty multiset with integers. Friends give her t queries, each of one of the following type:

 +  ai — add non-negative integer ai to the multiset. Note, that she has a multiset, thus there may be many occurrences of the same integer.
 -  ai — delete a single occurrence of non-negative integer ai from the multiset. It’s guaranteed, that there is at least one ai in the multiset.
? s — count the number of integers in the multiset (with repetitions) that match some pattern s consisting of 0 and 1. In the pattern, 0 stands for the even digits, while 1 stands for the odd. Integer x matches the pattern s, if the parity of the i-th from the right digit in decimal notation matches the i-th from the right digit of the pattern. If the pattern is shorter than this integer, it’s supplemented with 0-s from the left. Similarly, if the integer is shorter than the pattern its decimal notation is supplemented with the 0-s from the left.
For example, if the pattern is s = 010, than integers 92, 2212, 50 and 414 match the pattern, while integers 3, 110, 25 and 1030 do not.

Input
The first line of the input contains an integer t (1 ≤ t ≤ 100 000) — the number of operation Sonya has to perform.

Next t lines provide the descriptions of the queries in order they appear in the input file. The i-th row starts with a character ci — the type of the corresponding operation. If ci is equal to ‘+’ or ‘-’ then it’s followed by a space and an integer ai (0 ≤ ai < 1018) given without leading zeroes (unless it’s 0). If ci equals ‘?’ then it’s followed by a space and a sequence of zeroes and onse, giving the pattern of length no more than 18.

It’s guaranteed that there will be at least one query of type ‘?’.

It’s guaranteed that any time some integer is removed from the multiset, there will be at least one occurrence of this integer in it.

Output
For each query of the third type print the number of integers matching the given pattern. Each integer is counted as many times, as it appears in the multiset at this moment of time.

Examples
input
12
+ 1
+ 241
? 1
+ 361
- 241
? 0101
+ 101
? 101
- 101
? 101
+ 4000
? 0
output
2
1
2
1
1
input
4
+ 200
+ 200
- 200
? 0
output
1
Note
Consider the integers matching the patterns from the queries of the third type. Queries are numbered in the order they appear in the input.

1 and 241.
361.
101 and 361.
361.
4000.

題意:
給出三種輸入形式:
1.’+’添加一個數到數組
2.’-‘去掉數組中的某個數
3.’?’給出01字串,表示查詢的數的特徵(對應數位的奇偶情況,比喻250對應010,233對應011),查詢符合字串特徵的數的數量,如果長度不夠,就在字串前面補0.

解題思路:
把每個數按照特徵轉換成01,然後再把01串看做成位元,轉化成十進位數,然後實際存的是一類特徵數的個數.搜尋的時候也是把01串轉化成十進位數,然後檢索.

AC代碼:

#include<stdio.h>const int maxn = 1000005;int qdu[maxn];int main(){    int loop;    scanf("%d",&loop);    while(loop--)    {        char tmp1;        long long tmp2;        scanf(" %c %lld",&tmp1,&tmp2);        int sum = 0;        int k = 1;        while(tmp2)        {            sum += k*(tmp2%2);            tmp2 /= 10;            k <<= 1;        }        if(tmp1 == '+') qdu[sum]++;        else if(tmp1 == '-') qdu[sum]--;        else if(tmp1 == '?') printf("%d\n",qdu[sum]);    }    return 0;}