杭电acm1264

//据说使用线段树的 #include <stdio.h>#include <string.h>#define N 101int i, j, ans, buf[N][N];void print() {ans = 0;for(i=0; i<N; i++)for(j=0; j<N; j++)if(buf[i][j])ans ++;printf("%d\n", ans);}int main() {int ax, ay, bx, by, tmp;//memset(buf, 0, sizeof(buf));while(~scanf("%d%d%d%d", &ax, &ay, &bx, &by)) {if(ax==-1 && bx==-1 && ay==-1 && by==-1) {print();memset(buf, 0, sizeof(buf));continue ;}if(ax==-2 && bx==-2 && ay==-2 && by==-2) {print();break ;}if(ax>bx) {tmp = ax;ax = bx;bx = tmp;}if(ay>by) {tmp = ay;ay = by;by = tmp;}for(i=ax; i<bx; i++) {for(j=ay; j<by; j++) {buf[i][j] = 1;}}}return 0;}