#includevoid main(){int x,y;if(x>=1&&x<10)y=2*x-1;elseif(x>=10)y=3*x-11;printf("qing su ru x");scanf("%d",&x);printf("%d",y);}
if(x<1) y=x;else if(x<10) y=2*x-1;else y=3*x-11;
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