#include <stdio.h>

int main() {
    int n;
    while(scanf("%d",&n)!=EOF){
        double *p=(double *)malloc(sizeof(double)*n);
        for(int i=0;i<n;i++){
            scanf("%lf",&p[i]);
            getchar();
        }
        double max=p[0];
        double answer=p[0];
        for(int i=1;i<n;i++){
            answer=(answer+p[i])>p[i]? (answer+p[i]):(p[i]);
            if(answer>max) max=answer;
        }
        printf("%.0lf\n",max);
    }
    return 0;
}