Submission #832770

#	Time	Username	Problem	Language	Result	Execution time	Memory
832770		aymanrs	Sorting (IOI15_sorting)	C++14	74 / 100	1047 ms	18288 KiB

sorting

#include <bits/stdc++.h>
#include "sorting.h"
using namespace std;
int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[]) {
	if(is_sorted(S, S+N)) return 0;
	M = min(M, 4*N);
	int p[M], q[M];
	int R, l = 0, r = M-1, m, b = M;
	int cp[N];
	for(int i = 0;i < N;i++) cp[i] = S[i];
	while(l <= r){
		R = 0;
		for(int i = 0;i < N;i++) S[i] = cp[i];
		m = l+r>>1;
		for(int i = 0;i <= m;i++){
			if(is_sorted(S, S+N)) break;
			R++;
			swap(S[X[i]], S[Y[i]]);
			int opt[N];

			for(int j = 0;j<N;j++) opt[j]=j;
			for(int j = m;j > i;j--) swap(opt[X[j]], opt[Y[j]]);
			bool f = false;
			for(int j = 0;j < N;j++){
				if(S[j] != opt[j]){
					f = true;
					for(int k = j+1;k < N;k++) {
						if(S[k] == opt[j]) {
							p[R-1] = j;
							q[R-1] = k;
							swap(S[j], S[k]);
							break;
						}
					}
					break;
				}
			}
			if(!f) p[R-1] = q[R-1] = 0;
		}
		if(is_sorted(S, S+N)){
			for(int i = 0;i < R;i++) {
				P[i] = p[i];
				Q[i] = q[i];
			}
			b = R;
			r = m-1;
		} else l = m+1;
	}
	return b;
}

Compilation message (stderr)

sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:14:8: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   14 |   m = l+r>>1;
      |       ~^~

• Subtask 1: 8 / 8
• Subtask 2: 12 / 12
• Subtask 3: 16 / 16
• Subtask 4: 18 / 18
• Subtask 5: 20 / 20
• Subtask 6: 0 / 26