LeetCode - Two Sum

Leet Code - Two Sum

记录代码

/* Problem: * Given an array of integers, return indices of the two numbers such that they add up to a specific target.You may assume that each input would have exactly one solution.And you may not use the same element twice. */#include<stdio.h>#include<string.h>#include<malloc.h>#define HASH_LEN 1000typedef struct Data{    int value;    int index;    struct Data *next;}Data;typedef struct Hash{    Data *head;    Data *end;}Hash;void insertData(Hash *hash,Data *data);int searchData(Hash *hash,int value,int i);int *twoSum(int *nums,int numsSize,int target);int main(void){    int numsSize,target;    scanf("%d",&numsSize);    int nums[numsSize];    printf("Please input the data:\n");    for(int i=0;i<numsSize;i++)        scanf("%d",&nums[i]);    printf("Please input the target:\n");    scanf("%d",&target);    int *ans;    ans=twoSum(nums,numsSize,target);    if(ans)        for(int i=0;i<2;i++)            printf("%d ",*(ans+i));    else        printf("No answers.");    return 0;}void insertData(Hash *hash,Data *data){    int key=(unsigned int)(data->value)%HASH_LEN;    if(!hash[key].head){        hash[key].head=data;        hash[key].end=data;    }    else{        hash[key].end->next=data;        hash[key].end=data;    }}int searchData(Hash *hash,int value,int i){    int key=(unsigned int)value%HASH_LEN;    Data *p=hash[key].head;    while(p){        if(p->value==value&&p->index!=i)            return p->index;        p=p->next;    }    return 0;}int *twoSum(int *nums,int numsSize,int target){    int *ans=(int *)malloc(2*sizeof(int));    Hash hash[HASH_LEN];    memset(hash,0,sizeof(Hash)*HASH_LEN);    Data data[HASH_LEN];    memset(data,0,sizeof(Data)*HASH_LEN);    for(int i=0;i<numsSize;i++){        data[i].value=nums[i];        data[i].index=i;        insertData(hash,&data[i]);    }    for(int i=0;i<numsSize;i++){        int x=i;        int y=searchData(hash,target-nums[i],i);        if(y){            ans[0]=x<y?x:y;            ans[1]=x+y-ans[0];            break;        }        else            return NULL;    }    return ans;}