简单题

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
using namespace std;
#define maxn 100
int n, r;
int f[maxn], g[maxn];
void work(int p, int c)
{
for (int i = 0; i < c; i++)
g[i] = f[p + i];
for (int i = p - 1; i > 0; i--)
f[i + c] = f[i];
for (int i = 0; i < c; i++)
f[i + 1] = g[i];
}
int main()
{
//freopen("t.txt", "r", stdin);
while (scanf("%d%d", &n, &r), n | r)
{
for (int i = 1; i <= n; i++)
f[i] = n - i + 1;
for (int i = 0; i < r; i++)
{
int p, c;
scanf("%d%d", &p, &c);
work(p, c);
}
printf("%d\n", f[1]);
}
return 0;
}