POJ-1276 Cash machine multiple backpack binary optimization

Title Link: https://cn.vjudge.net/problem/POJ-1276

Test instructions

Too lazy to write their own to watch, sleepy hurriedly write this back to the dorm to sleep, tomorrow morning also to test.

Ideas

Binary optimization of multiple backpacks.
The idea is to split n items into log (m) items, which allows these items to be combined out of a 1~n original item, which is used in 01 backpacks.

Submission Process

WA	I don't understand num-=k.
AC

Code

#include <cstdio> #include <cstring> #include <algorithm>using namespace Std;const int maxn=1000+20,    MAXM=10+20, Maxc=1e5+20;int CASH[MAXM], NUM[MAXN], DP[MAXC], total, N;char str[500];void compknap (int. cost, int weight) { for (int i=cost; i<=total; i++) Dp[i]=max (Dp[i], dp[i-weight]+cost);} void Zeroknap (int cost, int. weight) {for (int i=total; i>=cost; i--) Dp[i]=max (Dp[i], dp[i-weight]+cost);} int main (void) {while (scanf ("%d%d", &total, &n) ==2) {for (int i=0; i<n; i++) scanf ("%d%d"                , &num[i], &cash[i]);        memset (DP, 0, sizeof (DP));            for (int i=0; i<n; i++) {if (num[i]*cash[i]>=total) {Compknap (Cash[i], cash[i]);                }else{int k=1;                    for (int k=1; k<num[i]; k*=2) {zeroknap (cash[i]*k, cash[i]*k);                Num[i]-=k;  } zeroknap (Cash[i]*num[i], cash[i]*num[i]);          }} printf ("%d\n", Dp[total]); } return 0;}

Time

	Memory	Length	Lang	submitted
47ms	552kB	1063	C++	2018-08-10 09:24:56

POJ-1276 Cash machine multiple backpack binary optimization