tips

use int till 10^9
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//print upto 3 decimal places

cout<<setprecision(3)<<fixed<<a<<endl; //#include <iomanip>
cout<<round(b*1000/n)/1000<<endl;

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//read string as input
char str[100000];
scanf("%s",str);
for(t=0;str[t]!='\0';t++); // t = length of string

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//read string till ':' delimiter by avoiding space
getline(cin,h,':');

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// string to number
int a=s[i]-'0';
string s="";
s+= digit+'0';

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