27 lines
555 B
C++
27 lines
555 B
C++
#include<cstdio>
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#include<cstring>
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#include<algorithm>
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using namespace std;
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const int maxn=100005;
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int n,a[maxn],s[maxn],q[maxn],l,r,f[maxn],g[maxn];
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int main()
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{
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#ifdef local
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freopen("pro.in","r",stdin);
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#endif
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scanf("%d",&n);
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for(int i=1;i<=n;i++) scanf("%d",&a[i]);
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reverse(a+1,a+1+n);
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for(int i=1;i<=n;i++) s[i]=s[i-1]+a[i];
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q[l=r=1]=0;
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for(int i=1;i<=n;i++)
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{
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while(l<r&&s[i]>=f[q[l+1]]+s[q[l+1]]) l++;
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f[i]=s[i]-s[q[l]];
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g[i]=g[q[l]]+1;
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while(l<=r&&s[i]+f[i]<=s[q[r]]+f[q[r]]) r--;
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q[++r]=i;
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}
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printf("%d\n",g[n]);
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return 0;
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} |