#include #include #include using namespace std; typedef pair coor; typedef struct{ int x; int y; }dir; const dir D[]={ {0,-1},{0,1},{-1,0},{1,0} }; int main(){ int W,H,N; scanf("%d%d%d",&W,&H,&N); vector >M(H*2+1); for(auto &e:M)e.resize(W*2+1); for(;N--;){ int n,x,y; scanf("%d%d",&n,&x); for(int i=0;i0)M[coory][coorx+1]++,M[coory][coorx+k*2+1]--; else M[coory][coorx-k*2+1]++,M[coory][coorx+1]--; }else{ k/=W; if(y-x>0)M[coory+1][coorx]++,M[coory+k*2+1][coorx]--; else M[coory-k*2+1][coorx]++,M[coory+1][coorx]--; } } } for(int i=1;i q; for(q.push({0,0});!q.empty();){ coor cur=q.front();q.pop(); if(cur==make_pair(W*2-2,H*2-2))return !printf("%d\n",M[cur.second][cur.first]-1); for(auto &d:D){ if(0<=cur.first+d.x&&cur.first+d.x