1 #include <bits/stdc++.h> 2 #define _for(i,a,b) for(int i = (a);i < b;i ++) 3 typedef long long ll; 4 using namespace std; 5 int N,m; 6 inline ll read() 7 { 8 ll ans = 0; 9 char ch = getchar(), last = ' '; 10 while(!isdigit(ch)) last = ch, ch = getchar(); 11 while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar(); 12 if(last == '-') ans = -ans; 13 return ans; 14 } 15 inline void write(ll x) 16 { 17 if(x < 0) x = -x, putchar('-'); 18 if(x >= 10) write(x / 10); 19 putchar(x % 10 + '0'); 20 } 21 int dp[26][30009]; 22 int a[2][30]; 23 int main() 24 { 25 N = read(),m = read(); 26 _for(i,1,m+1) 27 _for(j,0,2) 28 a[j][i] = read(); 29 memset(dp,0,sizeof(dp)); 30 _for(i,1,m+1) 31 { 32 _for(j,0,N+1) 33 { 34 if(a[0][i] <= j) 35 dp[i][j] = max(dp[i-1][j],dp[i-1][j-a[0][i]]+a[0][i]*a[1][i]); 36 else 37 dp[i][j] = dp[i-1][j]; 38 } 39 } 40 write(dp[m][N]); 41 return 0; 42 }