UVA 10783 - Odd Sum

  Odd Sum 

Given a range [a, b], you are to find the summation of all the odd integers in this range. For example, the summation of all the odd integers in the range [3, 9] is 3 + 5 + 7 + 9 = 24.

Input 

There can be at multiple test cases. The first line of input gives you the number of test cases, T ( 1T100). Then T test cases follow. Each test case consists of 2 integers a and b ( 0ab100) in two separate lines.

Output 

For each test case you are to print one line of output - the serial number of the test case followed by the summation of the odd integers in the range [a, b].

Sample Input 

21535

Sample Output 

Case 1: 9Case 2: 8

秒之

#include<cstdio>#include<iostream>#include<string>#include<vector>#include<map>#include<set>#include<algorithm>#include<cmath>#include <cstring>#include <queue>using namespace std;#define eps 1e-20#define MAXN 150#define outstars cout << "*********" << endl;int s[MAXN];int main(){    int T;    s[0] = 0;    s[1] = 1;    for(int i = 2 ; i <= 120 ; i++)    {        int x = i + i % 2 - 1;        s[i] = x;        while(x > 1)        {            x -= 2;            s[i] += x;        }        //cout << i << ' ' << s[i] << endl;    }    cin >> T;    for(int Case = 1 ; Case <= T ; Case ++)    {        int a , b;        scanf("%d%d",&a,&b);        printf("Case %d: %d\n",Case, s[b] - s[a - 1]);    }    return 0;}/**/