CodeForces 631C Print Check

#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
using namespace std;

const int maxn = 200000 + 10;
int n, m;
int a[maxn], ans[maxn];
int op[maxn], e[maxn];
int pos[maxn];
int first, last;
int flag;
int p;
int tot;

bool cmp(const int &a, const int &b)
{
return a>b;
}

int main()
{
while (~scanf("%d%d", &n, &m))
{
for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
for (int i = 1; i <= m; i++) scanf("%d%d", &op[i], &e[i]);
memset(ans, 0, sizeof ans);
tot = 0; memset(pos, -1, sizeof pos);
pos[m] = m;
for (int i = m - 1; i >= 1; i--)
{
pos[i] = pos[i + 1];
if (e[i] > e[pos[i + 1]]) pos[i] = i;
}

p = pos[1];
if (op[p] == 1){sort(a + 1, a + 1 + e[p]); flag = 1;}
else{sort(a + 1, a + 1 + e[p], cmp);flag = 2;}
first = 1; last = e[p];
for (int i = e[p] + 1; i <= n; i++) ans[i] = a[i], tot = tot + 1;
while (tot<n)
{
p = pos[p + 1]; if (p == -1) break;
if (first>last)
{
for (int i = last; i <= first - e[p]; i++) ans[n - tot] = a[i], tot = tot + 1;
last = first - e[p]+1;
}
else
{
for (int i = last; i >= first + e[p]; i--) ans[n - tot] = a[i], tot = tot + 1;
last = first + e[p] - 1;
}
if (op[p] != flag)
{
swap(first, last);
flag = op[p];
}
}
if (tot < n)
{
if (first <= last) for (int i = last; i >= first; i--) ans[n - tot] = a[i], tot = tot + 1;
else for (int i = last; i <= first; i++) ans[n - tot] = a[i], tot = tot + 1;
}

for (int i = 1; i <= n; i++) printf("%d ", ans[i]);
printf("\n");
}
return 0;
}