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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static void printchart(int size,char *chart,int curx,int cury){
for(int i=0;i<size;i++){
for(int j=0;j<size;j++){
if(cury==i&&curx==j)putchar('[');
else if(cury==i&&curx==j-1)putchar(']');
else putchar(' ');
putchar(".W#F"[(int)chart[size*i+j]]);
}
if(cury==i&&curx==size-1)putchar(']');
putchar('\n');
}
}
static int embiggen(int *sizep,char **chartp){
int size=*sizep;
char *chart=*chartp;
int newsize=2*size-1,d=(size-1)/2;
char *newchart=calloc(newsize*newsize,1);
for(int i=0;i<size;i++){
memcpy(newchart+newsize*(i+d)+d,chart+size*i,size);
}
free(chart);
*sizep=newsize;
*chartp=newchart;
return d;
}
static int virus1[4][2]={{2,3}, {0,0}, {0,1}, {0,0}};
static int virus2[4][2]={{1,3}, {2,0}, {3,1}, {0,2}};
static int simulate(int size,const char *origchart,int virus[4][2],int nsteps){
char *chart=malloc(size*size);
memcpy(chart,origchart,size*size);
int curx=size/2,cury=size/2,dir=0;
int ninf=0;
for(int iter=0;iter<nsteps;iter++){
if(curx<0||cury<0||curx>=size||cury>=size){
int d=embiggen(&size,&chart);
curx+=d; cury+=d;
}
int v=chart[size*cury+curx];
dir=(dir+virus[v][1])%4;
v=virus[v][0];
chart[size*cury+curx]=v;
if(v==2)ninf++;
switch(dir){
case 0: cury--; break;
case 1: curx++; break;
case 2: cury++; break;
case 3: curx--; break;
}
}
return ninf;
}
int main(void){
freopen("22.in","r",stdin);
char *line=NULL;
size_t linecap=0;
int size=getline(&line,&linecap,stdin)-1;
char *chart=malloc(size*size);
for(int i=0;i<size;i++)chart[i]=line[i]=='#'?2:0;
for(int i=1;i<size;i++){
getline(&line,&linecap,stdin);
for(int j=0;j<size;j++)chart[size*i+j]=line[j]=='#'?2:0;
}
int curx=size/2,cury=size/2;
printchart(size,chart,curx,cury);
printf("%d\n",simulate(size,chart,virus1,10000));
printf("%d\n",simulate(size,chart,virus2,10000000));
}
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