1 #include 
     
       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; 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 a[200039];22 23 int main()24 {25     n = read();26     _for(i,0,n)27         a[i] = read();28     29     int rnt = a[0];30     int trnt = a[0];31     _for(i,1,n)32     {33         if(trnt<0)34             trnt = a[i];35         else36             trnt += a[i];37         rnt = max(rnt,trnt);38     }39     write(rnt);40     return 0;41 }