两道的题型都是:给出现有的匹配,让你求匹配的权值最大时,改动的边数。
方法就是把边上标记,上标记的方法就是把权值扩大比N大的一个倍数,比如说N:50,那么我们就扩大55倍,原来已经存在的匹配边权值再加1,就这样,无论有原有匹的匹配边有多少条,一定要小于55,通过这样又标记出了没有改变的匹配边。求得ans/55时,这个值就是最大的匹配权值,ans%55就是没有改变的匹配边。
/*HDU 2853*/ #include <iostream> #include <cstdlib> #include <cstdio> #include <string> #include <cstring> #include <cmath> #include <vector> #include <queue> #include <algorithm> #include <map> #include <cctype> using namespace std; const int maxn = 60; const int INF = 0x3f3f3f3f; int n, m; int W[maxn][maxn]; int Lx[maxn], Ly[maxn]; int Left[maxn]; bool S[maxn], T[maxn]; bool match(int i) { S[i] = 1; for(int j = 1; j <= m; j++) if(Lx[i]+Ly[j] == W[i][j] && !T[j]) { T[j] = 1; if(!Left[j] || match(Left[j])) { Left[j] = i; return 1; } } return 0; } void update() { int a = INF; for(int i = 1; i <= n; i++) if(S[i]) for(int j = 1; j <= m; j++) if(!T[j]) a = min(a, Lx[i]+Ly[j]-W[i][j]); for(int i = 1; i <= n; i++) { if(S[i]) Lx[i] -= a; } for(int j = 1; j <= m; j++) { if(T[j]) Ly[j] += a; } } void KM() { memset(Left, 0, sizeof(Left)); memset(Lx, 0, sizeof(Lx)); memset(Ly, 0, sizeof(Ly)); for(int i = 1; i <= n; i++) { for(int j = 1; j <= m; j++) Lx[i] = max(Lx[i], W[i][j]); } for(int i = 1; i <= n; i++) { for(;;) { for(int j = 1; j <= m; j++) S[j] = T[j] = 0; if(match(i)) break; else update(); } } } inline void readint(int &x) { char c; c = getchar(); while(!isdigit(c)) c = getchar(); x = 0; while(isdigit(c)) x = x*10+c-'0', c = getchar(); } inline void writeint(int x) { if(x > 9) writeint(x/10); putchar(x%10+'0'); } int N, M; int sum; void read_case() { n = N, m = M; for(int i = 1; i <= N; i++) for(int j = 1; j <= M; j++) { readint(W[i][j]); W[i][j] *= 100; } sum = 0; for(int i = 1; i <= N; i++) { int x; readint(x); sum += W[i][x]; W[i][x] += 1; } } void solve() { read_case(); KM(); int ans = 0; for(int i = 1; i <= m; i++) if(Left[i]) ans += W[Left[i]][i]; int ans1 = N-ans%100, ans2 = ans/100 - sum/100; writeint(ans1), putchar(' '), writeint(ans2), puts(""); } int main() { while(~scanf("%d%d", &N, &M)) { solve(); } return 0; }
/*HDU 3315*/ #include <iostream> #include <cstdlib> #include <cstdio> #include <string> #include <cstring> #include <cmath> #include <vector> #include <queue> #include <algorithm> #include <map> #include <cctype> using namespace std; const int maxn = 100; const int INF = 0x3f3f3f3f; int n, m; int W[maxn][maxn]; int Lx[maxn], Ly[maxn]; int Left[maxn]; bool S[maxn], T[maxn]; bool match(int i) { S[i] = 1; for(int j = 1; j <= m; j++) if(Lx[i]+Ly[j] == W[i][j] && !T[j]) { T[j] = 1; if(!Left[j] || match(Left[j])) { Left[j] = i; return 1; } } return 0; } void update() { int a = INF; for(int i = 1; i <= n; i++) if(S[i]) for(int j = 1; j <= m; j++) if(!T[j]) a = min(a, Lx[i]+Ly[j]-W[i][j]); for(int i = 1; i <= n; i++) { if(S[i]) Lx[i] -= a; } for(int j = 1; j <= m; j++) { if(T[j]) Ly[j] += a; } } void KM() { memset(Left, 0, sizeof(Left)); memset(Lx, 0, sizeof(Lx)); memset(Ly, 0, sizeof(Ly)); for(int i = 1; i <= n; i++) { for(int j = 1; j <= m; j++) Lx[i] = max(Lx[i], W[i][j]); } for(int i = 1; i <= n; i++) { for(;;) { for(int j = 1; j <= m; j++) S[j] = T[j] = 0; if(match(i)) break; else update(); } } } inline void readint(int &x) { char c; c = getchar(); while(!isdigit(c)) c = getchar(); x = 0; while(isdigit(c)) x = x*10+c-'0', c = getchar(); } inline void writeint(int x) { if(x > 9) writeint(x/10); putchar(x%10+'0'); } int N; int V[maxn]; int H[maxn], P[maxn]; int A[maxn], B[maxn]; int check(int i, int j) { int Hi = H[i], Pi = P[j]; int d1 = A[i], d2 = B[j]; for(;;) { Pi -= d1; if(Pi <= 0) return 1; Hi -= d2; if(Hi <= 0) return 0; } return -1; } void read_case() { n = m = N; for(int i = 1; i <= N; i++) readint(V[i]); for(int i = 1; i <= N; i++) readint(H[i]); for(int i = 1; i <= N; i++) readint(P[i]); for(int i = 1; i <= N; i++) readint(A[i]); for(int i = 1; i <= N; i++) readint(B[i]); } void build() { for(int i = 1; i <= N; i++) for(int j = 1; j <= N; j++) { if(check(i, j) > 0) { W[i][j] = V[i]*100; } else { W[i][j] = -V[i]*100; } if(i == j) W[i][j] += 1; } } void solve() { read_case(); build(); KM(); int ans = 0; for(int i = 1; i <= m; i++) if(Left[i]) ans += W[Left[i]][i]; if(ans > 0) { int ans1 = ans/100; double ans2 = 1.0*(ans%100)/N * 100; printf("%d %.3lf%%\n", ans1, ans2); } else { printf("Oh, I lose my dear seaco!\n"); return ; } } int main() { while(~scanf("%d", &N) && N) { solve(); } return 0; }