POI - PA 2007 Encyclopedia [B]

30-03-10   11:10       Encyclopedia [B]      OK           10                                                           .


頗白癡的題目我說= =


說實話有點不值得Round 3的水準

就是給你一個由n個1    n個0組成的序列，每次交換相鄰兩個

問你把它轉成101010....   或010101....  最少要幾步










//***********************************

#include<stdio.h>
int in, n, pos, pos2;
long long ans, ans2;
long long abs(int a, int b){
	if(a> b)return (long long)a-b;
	return (long long)b-a;
}
int main(){
	scanf("%d", &n);
	pos= 1; pos2= 1;
	for(int i=0; i<2*n; i++){
		scanf("%d", &in);
		if(in== 0){
			ans+= abs(pos, i);
			pos+= 2;
		}else{
			ans2+= abs(pos2, i);
			pos2+= 2;
		}
	}
	printf("%lld\n", ans<ans2? ans: ans2);
}