Add day 2 part 2

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Dec 31, 2019, 5:16 AM

Z2RPGTOWKRMA2YKUJGN3OOPJIKHBEHPKOXPYCJ6UFIXRGKIDM7EQC

Dependencies

[2] TCCBGQEU 2019 day 1

Change contents

file addition: day2p2.c (----------)

[2.7]

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>

typedef struct ll {
int val;
struct ll *nxt;
} ll;

int step(int *prog, int *pc);

int* do_read(int *len);
int ll_length(ll *head);
ll* ll_read(void);
void ll_free(ll *head);
int* to_a(ll *head, int *len);

void main(void) {
int proglen = 0;
int pc = 0;
int *prog = NULL;
int *run = NULL;
int x = 0, y = 0;
prog = do_read(&proglen);
run = malloc(proglen * sizeof(int));
for(int i = 0; i < INT_MAX; i++) {
for(int j = 0; j <= i; j++) {
int t = i == j ? 1 : 2;
for(int s = 0; s < t; s++) {
if(s) {
x = j; y = i;
} else {
x = i; y = j;
}
memcpy(run, prog, proglen * sizeof(int));
run[1] = x;
run[2] = y;
pc = 0;
while(step(run, &pc)) {}
if(run[0] == 19690720){
printf("%d\n",100 * x + y);
goto found;
}
}
}
}
fprintf(stderr, "Solution not found\n");
found:
free(prog);
free(run);
}

int step(int *prog, int *pc) {
switch(prog[*pc]) {
case 1:
prog[prog[(*pc) + 3]] = prog[prog[(*pc) + 1]] + prog[prog[(*pc) + 2]];
*pc += 4;
return 1;
case 2:
prog[prog[(*pc) + 3]] = prog[prog[(*pc) + 1]] * prog[prog[(*pc) + 2]];
*pc += 4;
return 1;
default:
return 0;
}
}

int* do_read(int *len) {
ll* as_list = NULL;
int *r = NULL;
as_list = ll_read();
r = to_a(as_list, len);
ll_free(as_list);
return r;
}

int* to_a(ll *head, int *len) {
int *r = NULL;
int i = 0;
if(!head)
return NULL;
*len = ll_length(head);
r = malloc(*len * sizeof(int));
while(head) {
r[i++] = head->val;
head = head->nxt;
}
return r;
}

ll* ll_read(void) {
ll *head = NULL;
ll *cur = NULL;
ll *tmp = NULL;
int x;
while(!feof(stdin)) {
scanf("%d",&x);
scanf(",");
tmp = malloc(sizeof(ll));
tmp->val = x;
if(!head) {
head = tmp;
}
if(cur) {
cur->nxt = tmp;
}
cur = tmp;
}
return head;
}

int ll_length(ll *head) {
int r = 0;
while(head) {
r++;
head = head->nxt;
}
return r;
}

void ll_free(ll *head) {
ll *nxt;
while(head) {
nxt = head->nxt;
free(head);
head = nxt;
}
}