1 #include<iostream>
 2 #include<cstdio>
 3 
 4 using namespace std;
 5 
 6 int n,c,v,w[10001],a[10001],f[10001];
 7 
 8 int main() {
 9     scanf("%d%d%d",&v,&n,&c);
10     for(int i = 1;i <= n; i++)
11         scanf("%d%d",&w[i],&a[i]);
12     for(int i = 1;i <= n; i++) 
13         for(int j = c;j >= a[i]; j--)
14             f[j] = max(f[j],f[j-a[i]] + w[i]);
15     for(int i = 0;i <= c; i++)
16         if(f[i] >= v) {
17             printf("%d",c - i);
18             return 0;
19         }
20     printf("Impossible");
21     return 0;
22 }