POJ 3414 Pots

本来用string来记录状态，tle，于是改为用类似于并查集的方法记录。只记录 此次动作 和 上一个动作的位置。

中间又有一些低级失误，wa了n次。。orz

/*ID: immozer1PROG: ****LANG: C++*/#include <vector>#include <list>#include <map>#include <set>#include <deque>#include <stack>#include <bitset>#include <fstream>#include <algorithm>#include <functional>#include <numeric>#include <utility>#include <sstream>#include <iostream>#include <iomanip>#include <cstdio>#include <cmath>#include <cstdlib>#include <ctime>#include <cstring>using namespace std;struct Status {int l,r;};Status st[20000];//记录此次的动作int rec[20000];bool v[20000];//用了类似并查集的方法记录上一个动作的位置int father[20000];int bfs(int a,int b,int c){int top,end,tl,tr;top = end = 0;st[end].l = 0;father[end] = end;st[end++].r = 0;v[0] = true;while(top < end){if(st[top].l == c || st[top].r == c)return top;tl = st[top].l;tr = st[top].r;//分别对应fill(1),fill(2),drop(1),...,pour(2,1)if(tl != a && !v[150*a+tr]) {v[150*a+tr] = true;st[end].l = a;st[end].r = tr;father[end] = top;rec[end++] = 1;}if(tr != b && !v[150*tl+b]) {v[150*tl+b] = true;st[end].l = tl;st[end].r = b;father[end] = top;rec[end++] = 2;}if(tl != 0 && !v[tr]) {v[tr] = true;st[end].l = 0;st[end].r = tr;father[end] = top;rec[end++] = 3;}if(tr != 0 && !v[150*tl]) {v[150*tl] = true;st[end].l = tl;st[end].r = 0;father[end] = top;rec[end++] = 4;}int tmp;if(tl != a && tr != 0) {tmp = min(a-tl,tr);if(!v[(tl+tmp)*150+tr-tmp]) {v[(tl+tmp)*150+tr-tmp] = true;st[end].l = tl + tmp;st[end].r = tr - tmp;father[end] = top;rec[end++] = 5;}}if(tl != 0 && tr != b) {tmp = min(tl,b-tr);if(!v[(tl-tmp)*150+tr+tmp]) {v[(tl-tmp)*150+tr+tmp] = true;st[end].l = tl - tmp;st[end].r = tr + tmp;father[end] = top;rec[end++] = 6;}}top++;}return 0;}int main(){int a,b,c;cin >> a >> b >> c;int sp[10000],end,now;now = bfs(a,b,c);end = 0;//将并查集的元素取出,记录while(now != father[now]) {sp[end++] = now;now = father[now];}if(end == 0) {cout << "impossible" << endl;return 0;}string y;cout << end << endl;for(int i = end-1; i >= 0; i--) {switch(rec[sp[i]]) {case 1:y = "FILL(1)";break;case 2:y = "FILL(2)";break;case 3:y = "DROP(1)";break;case 4:y = "DROP(2)";break;case 5:y = "POUR(2,1)";break;default:y = "POUR(1,2)";}cout << y << endl;}return 0;}