腾讯编程马拉松初赛第一场（2013.3.20）

#include <cstdio>
#include <vector>
#include <iostream>

using namespace std;

int T;
int a,b;
unsigned long long f[50][300];

int main(){
while (scanf("%d %d %d", &a, &b, &T)==3){
int need=b-a+1;
int can=T/30;
T=T%30;
need=need+can;
if (T>=15) ++can;
if (need<0) need=0;
for (int i=0; i<=can; ++i)
for (int j=0; j<=need; ++j)
f[i][j]=0;
f[0][0]=1;
for (int i=0; i<can; ++i)
for (int j=0; j<=need; ++j)
if (f[i][j]){
//printf("%d %d\n", i,j);
for (int k=1; k<=3; ++k){
int t=j+k;
if (t>need) t=need;
f[i+1][t]+=f[i][j];
}
}
cout<<f[can][need]<<endl;
}
}