POJ-2503 babelfish hash table

The hash table is easy to use because map is faster and easier.

Multiply each character string by the corresponding position and then perform the hash operation.

This problem also encountered a problem. During string copying, because of the direct sizeof (in) because the in function overwrites the global in, in is a pointer variable, so it is not 15 but 4. Each time it is assigned only four bytes, it must be wrong.

The Code is as follows:

#include <cstring>#include <cstdio>#include <cstdlib>#define MOD 2000003using namespace std;char s[50], in[15], out[15];int head[2000003], idx;struct Node{    char w[15], t[15];    int next;}e[1000005];void Hash(char *in, char *out){    int key = 0;    int length = strlen(in);    for (int i = 0; i < length; ++i) {        key += in[i] * (i+1);    }    key %= MOD;    ++idx;    strcpy(e[idx].w, in);    strcpy(e[idx].t, out);    e[idx].next = head[key];    head[key] = idx;}int find(char *in){    int length = strlen(in), key = 0;    for (int i = 0; i < length; ++i) {        key += in[i] * (i+1);    }    key %= MOD;    for (int i = head[key]; i != -1; i = e[i].next) {        if (!strcmp(in, e[i].w)) {            return i;        }    }     return -1;}int main(){    int ans;    memset(head, 0xff, sizeof (head));    idx = -1;    while (gets(s)) {        int length = strlen(s);        if (length != 0) {            sscanf(s, "%s %s", out, in);            Hash(in, out);        }        else {            while (gets(s)) {                ans = find(s);                if (ans == -1) {                    puts("eh");                }                    else {                    printf("%s\n", e[ans].t);                }            }        }    }    return 0;}