Submission #500741

#	Time	Username	Problem	Language	Result	Execution time	Memory
500741		sewon1407	공장 (KOI13_factory)	C11	20 / 20	373 ms	15072 KiB

factory

#include <stdio.h>

int n;
int seg[2100000];
int indexes[1000001];

int sum(int from, int to, int node, int start, int end) {
    if(from > end || to < start) return 0;
    if(from <= start && end <= to) return seg[node];
    int mid = (start+end)/2;
    return sum(from, to, node*2, start, mid)+sum(from, to, node*2+1, mid+1, end);
}

void update(int i, int diff, int node, int start, int end) {
    if(i < start || i > end) return;
    seg[node] += diff;
    int mid = (start+end)/2;
    if(start == end) return;
    update(i, diff, node*2, start, mid);
    update(i, diff, node*2+1, mid+1, end);
}

int main() {
    int t, p;
    unsigned long long cnt = 0;
    
    scanf("%d", &n);
    for(int i=0; i<n; i++) {
        scanf("%d", &t);
        indexes[t] = i;
    }
    for(int i=0; i<n; i++) {
        scanf("%d", &t);
        p = indexes[t];
        cnt += sum(p+1, n-1, 1, 0, n-1);
        update(p, 1, 1, 0, n-1);
    }
    printf("%llu", cnt);
}

Compilation message (stderr)

factory.c: In function 'main':
factory.c:27:5: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   27 |     scanf("%d", &n);
      |     ^~~~~~~~~~~~~~~
factory.c:29:9: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   29 |         scanf("%d", &t);
      |         ^~~~~~~~~~~~~~~
factory.c:33:9: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |         scanf("%d", &t);
      |         ^~~~~~~~~~~~~~~

• Subtask 1: 2.2 / 2.2
• Subtask 2: 3.4 / 3.4
• Subtask 3: 3.8 / 3.8
• Subtask 4: 4.8 / 4.8
• Subtask 5: 5.8 / 5.8