50190. Set Sorting and Searching
難度：4/5
比較有趣的點是，你為了qsort而寫的cmp fucntion，也可以拿進去給binary-search給comparsion用。1
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76#include <stdio.h>
#include <stdlib.h>
#define min(a,b) ((a)<(b)?(a):(b))
typedef struct{
int* arr;
int n;
} set;
int cmp_arr(const void* a, const void* b){
return *(int*)b - *(int*)a;
}
int cmp_set(const void* aa, const void* bb){
set* a = (set*)aa;
set* b = (set*)bb;
int min_len = min(a->n, b->n);
for(int i = 0; i < min_len; i++){
if(a->arr[i] != b->arr[i]){
return a->arr[i] - b->arr[i];
}
}
if(a->n == b->n) return 0;
else if(a->n == min_len) return -1;
else return 1;
}
void make_set(set* s){
scanf("%d", &s->n);
s->arr = (int*) malloc(sizeof(int) * s->n);
for(int i = 0; i < s->n; i++){
scanf("%d", &s->arr[i]);
}
qsort(s->arr, s->n, sizeof(int), cmp_arr);
}
void free_set(set* s){
free(s->arr);
}
int binary_search(set set_arr[], set* target, int n){
int l = 0, r = n - 1;
while(l <= r){
int m = (l + r) / 2;
int rtv = cmp_set(&set_arr[m], target);
if(rtv == 0) return m;
else if(rtv < 0) l = m + 1;
else r = m - 1;
}
return -1;
}
int main(){
int n; scanf("%d", &n);
set set_arr[10000];
for(int i = 0; i < n; i++){
make_set(&set_arr[i]);
}
qsort(set_arr, n, sizeof(set), cmp_set);
// for(int i = 0; i < n; i++){
// for(int j = 0; j < set_arr[i].n; j++){
// printf("%d ", set_arr[i].arr[j]);
// }
// printf("\n");
// }
int q; scanf("%d", &q);
while(q--){
set target;
make_set(&target);
int rtv = binary_search(set_arr, &target, n);
printf("%d\n", rtv);
free_set(&target);
}
}