sicily 2011

刚开始做是对每一组数据直接进行bfs，结果TLE，后来改成先对所有情况进行bfs，然后直接由康拓展开输出答案，还是TLE。。后来，不用cin cout流。。AC...

#include <cstdio> #include <cstring> using namespace std; struct node { int s[9]; int step; }q[362880]; int ans[362880]; int init[9]; int tar[9] = {1, 2, 3, 4, 5, 6, 7, 8, 9}; int fac[9]; bool isUsed[362880]; void setFac() { fac[0] = fac[1] = 1; for(int i = 2; i <= 8; i++) fac[i] = fac[i - 1] * i; } int getID(int *data) { int id = 0; for(int i = 0; i < 9; i++) { int k = 0; for(int j = i + 1; j < 9; j++) { if(data[j] < data[i]) k++; } id += fac[9 - i - 1] * k; } return id; } void bfs() { node front; memset(isUsed, false, sizeof(isUsed)); memcpy(front.s, tar, sizeof(tar)); front.step = 0; q[0] = front; int id = getID(tar); isUsed[id] = true; ans[id] = 0; int beg = 0, end = 1; while(beg < end) { node tmp; tmp.step = q[beg].step + 1; tmp.s[0] = q[beg].s[1]; tmp.s[1] = q[beg].s[4]; tmp.s[2] = q[beg].s[2]; tmp.s[3] = q[beg].s[0]; tmp.s[4] = q[beg].s[3]; tmp.s[5] = q[beg].s[5]; tmp.s[6] = q[beg].s[6]; tmp.s[7] = q[beg].s[7]; tmp.s[8] = q[beg].s[8]; id = getID(tmp.s); if(!isUsed[id]) { q[end++] = tmp; ans[id] = tmp.step; isUsed[id] = true; } tmp.s[0] = q[beg].s[0]; tmp.s[1] = q[beg].s[2]; tmp.s[2] = q[beg].s[5]; tmp.s[3] = q[beg].s[3]; tmp.s[4] = q[beg].s[1]; tmp.s[5] = q[beg].s[4]; tmp.s[6] = q[beg].s[6]; tmp.s[7] = q[beg].s[7]; tmp.s[8] = q[beg].s[8]; id = getID(tmp.s); if(!isUsed[id]) { q[end++] = tmp; ans[id] = tmp.step; isUsed[id] = true; } tmp.s[0] = q[beg].s[0]; tmp.s[1] = q[beg].s[1]; tmp.s[2] = q[beg].s[2]; tmp.s[3] = q[beg].s[4]; tmp.s[4] = q[beg].s[7]; tmp.s[5] = q[beg].s[5]; tmp.s[6] = q[beg].s[3]; tmp.s[7] = q[beg].s[6]; tmp.s[8] = q[beg].s[8]; id = getID(tmp.s); if(!isUsed[id]) { q[end++] = tmp; ans[id] = tmp.step; isUsed[id] = true; } tmp.s[0] = q[beg].s[0]; tmp.s[1] = q[beg].s[1]; tmp.s[2] = q[beg].s[2]; tmp.s[3] = q[beg].s[3]; tmp.s[4] = q[beg].s[5]; tmp.s[5] = q[beg].s[8]; tmp.s[6] = q[beg].s[6]; tmp.s[7] = q[beg].s[4]; tmp.s[8] = q[beg].s[7]; id = getID(tmp.s); if(!isUsed[id]) { q[end++] = tmp; ans[id] = tmp.step; isUsed[id] = true; } beg++; } } int main() { setFac(); bfs(); while(scanf("%d", &init[0]) == 1){ for(int i = 1; i < 9; i++) scanf("%d", &init[i]); printf("%d/n", ans[getID(init)]); } return 0; }