# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
57455 | leejseo | 공장 (KOI13_factory) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
typedef long long lld;
int X[1000001], N;
vector<int> L;
vector<int> temp;
void input(){
scanf("%d", &N);
int val;
for (int i=0; i<N; i++){
scanf("%d", &val);
X[val] = i;
}
for (int i=0; i<N; i++){
scanf("%d", &val);
L.push_back(X[val]);
}
L.push_back((int) 1e9);
}
lld merge_sort(int fr, int ed){
if (ed <= fr+3){
lld ans = 0;
for (int i=fr; i<=ed; i++){
for (int j=fr; j<i; j++){
if (L[j] > L[i]) ans++;
}
}
for (int i=fr; i<=ed; i++){
for (int j=fr; j<i; j++){
if (L[j] > L[i]){
L[i] ^= L[j];
L[j] ^= L[i];
L[i] ^= L[j];
}
+ }
}
//printf("%d %d %lld\n", fr, ed, ans);
return ans;
}
int mid = (fr + ed) >>1;
lld val = merge_sort(fr, mid) + merge_sort(mid+1, ed);
int lo = 0, hi = mid+1;
while (lo < mid+1 || hi < ed+1){
//printf("%d %d\n", lo, hi);
if (hi > ed || (lo < mid+1 && L[lo] < L[hi])){
temp.push_back(L[lo++]);
continue;
}
else{
temp.push_back(L[hi++]);
val += (lld) mid - lo + 1;
continue;
}
}
for (int i=0; i<ed-fr+1; i++){
L[i+lo] = temp[i];
}
temp.clear();
//printf("%d %d %lld\n", fr, ed, val);
return val;
}
int main(void){
input();
//for (int i=0; i<N; i++){
// printf("%d ", L[i]);
//}
//printf("\n");
lld ans = merge_sort(0, N-1);
printf("%lld\n", ans);
}