man!what can I say!Ac out!
#include<bits/stdc++.h>
#include <cctype>
using namespace std;
int t,m;
int c[25],v[25];
int dp[25][30005];
int main(){
cin>>t>>m;
for(int i=1;i<=m;i++){
cin>>c[i]>>v[i];
}
for(int i=1;i<=m;i++){
for(int j=1;j<=t;j++){
dp[i][j] = dp[i-1][j];
if(j>=c[i]) dp[i][j] = max( dp[i-1][j] , dp[i-1][j-c[i]]+v[i]*c[i]);
}
}
cout<<dp[m][t];
