#include <stdio.h>
int main()
{
int k, n , w;
scanf("%d%d%d", &k, &n, &w);
int ans=(k*((w*(w+1))/2))-n;
if(ans>0)
printf("%d\n", ans);
else
printf("%d\n", 0);
return 0;
}
#include <stdio.h>
int main()
{
int k, n , w;
scanf("%d%d%d", &k, &n, &w);
int ans=(k*((w*(w+1))/2))-n;
if(ans>0)
printf("%d\n", ans);
else
printf("%d\n", 0);
return 0;
}
转载于:https://www.cnblogs.com/ozxics/p/10915864.html