Add Coldesy.cpp for Codeforces problem 1560

Implement Coldesy problem solution from Codeforces.

Author: Coldesy

Problems/Mathematics/Day-01/sol/Coldesy/Coldesy.cpp

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+//https://codeforces.com/contest/1560/submission/355205808
+//time complexity:O(t)
+//space complexity:O(1)
+#include <iostream>
+using namespace std;
+
+int main()
+{
+    int t;
+    cin>>t;
+    while(t--){
+        int a,b,c;
+        cin>>a>>b>>c;
+        int len;
+        if(a>b){
+            len=a-b;
+            len=2*len;
+        }               // staring at opposite end means both of them divide the circle 
+                        // in exact half so we substract them and multiply by 2 to get exact length
+        else {
+           
+            len=b-a;
+            len=2*len;
+        
+        }
+        if(a<=len&&b<=len&&c<=len){//a,b,c ofcourse cannot be greater than length
+            if(c+(len/2)>len){
+                cout<<c-(len/2)<<endl;//c will either stare at +n/2 or -n/2
+            }
+            else{
+                cout<<c+(len/2)<<endl;
+            }
+        }
+        else{cout<<-1<<endl;}
+    }
+
+    return 0;
+}