散列

//运用哈希时，将哈希函数封装成一个函数，并在输入数据时直接转化数据映射到哈希数组内
//整数哈希

#include<cstdio>

const int maxn=10000;
int hashtable[maxn]={0};

int main(void){
    int n,m,x;
    scanf("%d%d",&n,&m);
    for(int i=0;i<n;i++){
        scanf("%d",&x);
        hashtable[x]++;
    }
    for(int i=0;i<m;i++){
        scanf("%d",&x);
        printf("%d",hashtable[x]);
    }
    return 0;
}

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//字符串哈希

#include<cstdio>

int hashFunc(char S[],int len){
    int id=0;
    for(int i=0;i<len;i++){
        if(S[i]>='A'&&S[i]<='Z')
            id=id*62+S[i]-'A';
        else if(S[i]>='a'&&S[i]<='z')
            id=id*62+S[i]-'z';
        else if(S[i]>='0'&&S[i]<='9')
            id=id*62+S[i]-'0';
    }
    return id;
}

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